So, Celtic start their Europa League with a decent point away to Ajax but there will be a few what-ifs since Ronny Deila's men were looking comfortable at 2-1 before Emilio Izaguirre's red card.
We'll be back with more live action from the Scottish Premiership over the weekend. Goodnight and thanks for your company.
And more from Ronny Deila
"We are a team and we win and lose together. Emilio Izaguirre does not have a bad record for red cards and he was having a good game before the sending off. He was keeping their best player quiet."
More from Ronny Deila
"It was a very good delivery [for the second Ajax goal] but it's something we need to work on; we need to get to the ball first."
Celtic manager Ronny Deila
"We had a great attitude and I'm very proud of the boys. We had good control before the sending off. When we went to 10 men we were in trouble and I think a draw is okay."
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Former Celtic striker Scott McDonald on Sportsound
"Celtic were the better team after the interval and you were waiting for them to get a third goal on the break because Ajax were pushing so many bodies forward. Then came the red card and it changed everything."
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Former Celtic goalkeeper Pat Bonnar on Sportsound
"I don't know if this zonal thing is working for Celtic, they are giving away far too many goals from set-pieces. It's costing them every week and you can't dismiss that"
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It has to be remembered that Davy Klaassen did make a mess of two good opportunities for Ajax in the second half, while Arkadiusz Milik headed over from close range, so the home side will think a draw was the least they deserved.
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I'm sure Celtic fans would have taken a draw prior to kick-off but this was a great opportunity to get three points on the board in week one of the Europa League.
The Scottish champions have only won twice in their last 16 away days in Europe - and both of those came in Iceland.
Celtic manager Ronny Deila on BT Sport
"We have been through a tough period. This is a good start. Good defence and good organisation. The confidence will come. When we played 11 v 11, they didn't have too many chances."
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There was something of a shock in Group A's other match with Molde winning 3-1 away to Fenerbahce.
Join the debate at #bbcscotfootball
MBEHAN on Twitter: "Celtic pressing the self destruct button again, why wasn't a proper left back signed during transfer window, #bbcscotfootball"
Marco Silva: "Izaguirre, as always, ends up being a liability #bbcscotfootball"
Andrew Priestley: "Before kick-off Celtic would definitely have taken a draw away to Ajax to start, but at FT it's a disappointing result. #bbcscotfootball"
FULL-TIME
Ajax 2-2 Celtic
A point away from home against the Dutch league leaders doesn't sound too bad does it? But Celtic were looking comfortable at 2-1 before Emilio Izaguirre was sent packing for a second booking on 74 minutes.
Kris Commons made the difference for Celtic, setting up first-half goals for Nir Bitton and Mikael Lustig.
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We're into added time in stoppage time...
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Celtic are temporarily reduced to nine men as Nir Bitton limps off but he's not away for long and he's back in the thick of the action as the visitors dig in.
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Ajax pump the ball long into the penalty area and it lands up in the arms of Craig Gordon. Will Ajax get another chance in the remaining couple of minutes?
CLOSE!
The board goes up showing four minutes of stoppage-time just as Arkadiusz Milik heads over the top from close range.
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We're into the 89th minute now. Can 10-man Celtic hold on for what would be a very useful point?
Join the debate at #bbcscotfootball
Chris Williams on Twitter: "#bbcscotfootball What the hell did I just say about zonal marking?!!!!!! Doesn't work Ronny, stop doing it."
GOAL
Ajax 2-2 Celtic (Schone)
This guy loves a goal against Celtic... Having scored in both of the 2013 Champions League meetings, Lasse Schone has done it again to draw Ajax level. The Danish substitute powers in a dangerous free-kick from out on the left and everyone misses it, including an unconvincing Craig Gordon.
SUBSTITUTION
A depleted and tiring Celtic are now hanging on grimly, packing men along their 18 yard line as Kris Commons goes off to be replaced by defender Saidy Janko.
HITS THE WOODWORK
Craig Gordon is hesitant as Mitchell Dijks gets his head to a deep cross and the ball comes off the inside of the post. The Celtic goalkeeper redeems himself by clawing the loose ball away as a cluster of players throw themselves at it. A narrow escape for the visitors...
CLOSE!
Ajax really should be level as Davy Klaassen rises to meet the ball in a central position maybe 10 yards out but he skews and awkward header narrowly wide.
SUBSTITUTION
Ten-man Celtic also make a change and it's James Forrest who is sacrificed for Tyler Blackett, who will fill in for the prematurely departed Emilio Izaguirre.
SUBSTITUTION
Ajax swap a Dane for Dane as goalscorer Viktor Fischer is replaced by Lasse Schone, who scored in each of the 2013 meetings with Celtic.
RED CARD
A now Emilio Izaguirre is off! What was the full-back thinking of as he chopped the legs away from Anwar El Ghazi?
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Celtic pair Emilio Izguirre and Stefan Johansen, both on yellow cards, clatter into opponents in quick succession, drawing weak claims for further action from the home side.
SUBSTITUTION
Celtic are forced into a change as Mikael Lustig limps off and Efe Ambrose comes on to take over at right-back. The big Nigerian is involved right away as his uncertain touch forces Craig Gordon to look lively and come running to smother.
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Upset-o-clock in Group A's other match: Molde are now 3-1 up at Fenerbahce, with Martin Linnes scoring on 64 minutes.
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Celtic spring another counter-attack and Stefan Johansen cuts in from the right to try and find Kris Commons at the near post bit the pass is cut out by Thulani Serero. Leigh Griffiths then has a pop from distance, with Jasper Cillessen holding on to the skidding ball.
SUBSTITUTIONS
Ajax make a couple of changes, with Daley Sinkgraven and Amin Younes making way for Thulani Serero and Arkadiusz Milik.
Join the debate at #bbcscotfootball
John Everyman on Twitter: "In my view, Commons & Forrest are the 2 best players on the team & should be on the pitch in all but the rare circumstance #bbcscotfootball"
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Kris Commons chips a cute ball over the top of the Ajax defence for Leigh Griffiths to run on to. The angle is tight and the striker is stretching as he volleys into the side-netting.
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Tom English
BBC Scotland at the Amsterdam Arena
"Kris Commons underlying the madness of the decision to leave him on the bench at Aberdeen on Saturday. Two assists so far and every time he stands over a corner Ajax gulp hard. His deliveries are causing the home team huge trouble."
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Celtic defender Mikael Lustig gets his head to another Kris Commons corner but can only steer the ball wide. The home fans are growing more and more disgruntled.
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Molde take the lead against Fenerbahce again, with Mohammed Elyounoussi on target. It's 2-1 to the Norwegians now.
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Celtic cause more problems from a Kris Commons corner, with James Forrest having two shots blocked in the area.
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A few holes appear in the Celtic defence but the visitors are let off the hook as Davy Klaassen attempts a fancy flick when he had time and space to let fly with a shot from the edge of the box.
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The impressive Amsterdam ArenA is close to full but the home fans have been pretty quiet. Can Celtic keep it that way?
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Ajax exert some pressure and win a corner in unusual circumstances as goalkeeper Craig Gordon clips the heels of team-mate Emilio Izaguirre as he shapes to kick clear. The set-piece comes to nothing, sparing the Celtic duo any further embarrassment.
KICK-OFF
The second half is up and running. No changes in personnel for either side.
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The teams are back out. More of the same for Celtic, although they would make life easier for themselves if they improve their ball retention.
Join the debate at #bbcscotfootball
Andy Craig on Twitter: "Has Ronny Deila finally realised that Commons is our best player? 2 assists and hopefully more to come. #bbcscotfootball"
Andy adds: "Celtic are a different team with Commons playing. Best Celtic player by a country mile. Hope Ronny sees that from now on. #bbcscotfootball"
MBEHAN chips in: "Celtic so much better with Commons in the side countless goals & assists in the last few years #bbcscotfootball"
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Kris Commons hasn't started too many games this season but the midfielder has made a huge contribution tonight, setting up both goals. Are Celtic a better team with the 32-year-old playing? Use #bbcscotfootball on Twitter to let me know what you think.
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Elsewhere in Group A, Molde's lead didn't last long, with Fenerbahce drawing level before half-time thanks to former Manchester United winger Nani.
HALF-TIME
Ajax 1-2 Celtic
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That will do nicely for Celtic. The home side have had most of the ball but goals from Nir Bitton and Mikael Lustig have the visitors in front.
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Ajax are at sixes and sevens every time Celtic fire a delivery into the penalty area. Can Celtic bring Jan Vennegoor of Hesselink or Chris Sutton out of retirement for the second half? Those guys would have a field day against this home defence.
GOAL
Ajax 1-2 Celtic (Lustig)
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Simple as you like. Kris Commons pings in a corner kick and Mikael Lustig attacks it well to nod the visitors back in front. Leigh Griffiths will be feeling a bit better about that miss.
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Lone striker Leigh Griffiths has not seen much of the ball this evening but he's just blown a great chance for Celtic!
James Forrest is allowed to scurry free from a throw-in and cuts the ball back for Griffiths right in front of goal about five yards out but the shot is hopelessly scuffed and is saved by Cillessen via a slight deflection off a defender.
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A bit of a surprise brewing in Turkey as Molde take the lead against Group A favourites Fenerbahce. Tommy Hoiland with the goal from the penalty spot.
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Tom English
BBC Scotland at the Amsterdam Arena
"Ajax growing into this game after Fischer's equaliser. Celtic can't keep the ball. Any time they get it, they give it away instantly. Asking for trouble against a decent, but beatable, side."
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Kris Commons swings the set-piece deep into the penalty area but it floats out of play, with Nir Bitton claiming that he was being held back by a defender.
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A bit of respite for Celtic as they make ground in the opposition half and Kris Commons is bundled over to win a free-kick. Get the big men up...
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Former Celtic goalkeeper Pat Bonnar on Sportsound
"Celtic are defending well enough in numbers but they are making a couple of passes then just kicking it clear and giving it away. Ajax are much more controlled in their passing."
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Celtic are giving the ball away too cheaply, with Stefan Johansen the culprit this time. Nemanja Gudelj strides forward to have a shot but is well off target with his effort.
GOAL
Ajax 1-1 Celtic (Fischer)
The Dutch side draw level with a lovely goal as Amin Younes drives forward and his pass is cleverly back-heeled by Davy Klaassen into the path of Viktor Fischer, who steers a precise shot low into the corner from the edge of the penalty box.
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PICK IT OUT!
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Have a look at Nir Bitton's early goal for Celtic. It was a peach of a strike from the big Israel midfielder.
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Ajax are seeing more and more of the ball but Craig Gordon is yet to be seriously troubled. Amin Younes scuffs a shot in from the left and the Scotland international goalkeeper flops on it at his near post to eat up a few seconds.
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Nice footwork from Anwar El Ghazi as the Ajax midfielder drifts in along the byeline from the right but two defenders take the sting out of the shot and Dedryk Boyata completes the clearance with a firm header.
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A wee scare for the visitors as a pass from Davy Klaassen is cut out by Jozo Simunovic and, with Celtic keeper Craig Gordon going the other way, the ball drifts past the post by four or five feet. The resulting corner from Ajax is a stinker.
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The Ajax build-up has been ponderous so far, allowing Celtic to pack men behind the ball and cope comfortably.
GOAL
Ajax 0-1 Celtic (Bitton)
What a start for Celtic. The high-pressing works a treat as Stefan Johansen wins the ball deep in the Ajax half, Kris Commons then shuffles past an opponent and slips a pass through for Nir Bitton to arrow a low strike into the far corner.
The ball was bulging in the net before goalkeeper Jasper Cillessen could even move...
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Much better from Simunovic as he brushes Nemanja Gudelj off the ball to win possession. That could be an interesting Croatia - Serbia contest.
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Not a great first touch for Celtic new boy Jozo Simunovic as the big defender sprays a pass straight into touch...
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Ajax have not really got a recognised striker on the pitch but it looks like Davy Klaassen will play in the most advanced position.
KICK-OFF
A peep of the whistle from Italian referee Luca Banti and Celtic get the game started...
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Group A rivals Fenerbahce and Molde meet in Turkey tonight, so we'll keep you up to date with any goals in that one.
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The teams are in the tunnel. Celtic are kitted out in an extremely high-viz fluorescent yellow strip. Ajax in their famous white and red.
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These sides have played eight competitive matches, with Celtic leading the head-to-head with four wins to three. The last meeting was a Champions League group match in November 2013, with Lasse Schone scoring the only goal in Amsterdam to give Ajax three points.
The Danish midfielder, on the bench tonight, was on target in Glasgow that season too but only after James Forrest and Baram Kayal had netted for a home win.
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Celtic captain Scott Brown
[Talking last night] "We have let ourselves down recently and we have to just go on and show more willingness to win games and finish teams off.
"We know we can play better. We have to believe in ourselves a lot more.
"We have the players in the dressing room who can do it. We need a little bit of luck as well.
"Football is all about little details. I think if we get that one goal and get the second goal and go on, it builds confidence throughout the team and fans and they put trust in you."
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Tom English
BBC Scotland at the Amsterdam Arena
"Ajax team is remarkably young - two teenagers in the defence, only one player over the age of 23, average age 21.5. You can't win anything with kids. Hmmm."
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Of course, Ajax head coach Frank de Boer did spend some time in Scotland, playing 17 games for Rangers in season 2003-04. He was twice on the losing side at Celtic Park in that time.
This is what he said ahead of tonight's tie: "Both clubs also have a nice history, but that does not count anymore.
"Celtic are always the favourite in their own league, especially now Glasgow Rangers play in a lower league. We are also favourites as well, and are also required to play good football.
"Celtic can make it tricky for anyone. I am confident that we can win, but it will be difficult."
Join the debate at #bbcscotfootball
GET INVOLVED
We'd love to hear your thoughts as the action unfolds in Amsterdam. You know the Twitter drill, use #bbcscotfootball
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Ajax finished a long way behind PSV Eindhoven in the Eredivisie last season, having won the previous four titles. Frank de Boer's men have made a good start this time and sit top with four wins and a draw from their first five outings.
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Motherwell striker Scott McDonald, formerly of Celtic, is on the BBC Radio Scotland team this evening and he wants to see Kris Commons in a central position behind striker Leigh Griffiths.
"I think Kris is strongest in the number 10 role and there is always the question of does he have the legs to do a job out wide in Europe," says the Australian.
LINE-UPS FROM THE AMSTERDAM ARENA
Ajax: Cillessen, Tete, Veltman, Riedewald, Dijks, Gudelj, Fischer, Sinkgraven, El Ghazi, Younes, Klaassen. Subs: Boer, Van Rhijn, van der Hoorn, Milik, Schone, Serero, Viergever.
The Celtic back four will be kept on their toes by a youthful Ajax side, with the Amsterdam club's famous academy continuing to churn out top talents.
Anwar El Ghazi and Daley Sinkgraven are fresh faces to look out for tonight.
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Much of the frustrated finger-pointing has been in the direction of Celtic's defence. The Scottish champions raced into a 2-0 lead at home to Malmo, eventually winning 3-2, before a disappointing display in the return leg, while Aberdeen were down to 10 men when they grabbed a late winner with a simple, high ball into the box.
Virgil van Dijk has been sold to Southampton, although he did not exactly cover himself in glory in those two games against Malmo, and Charlie Mulgrew sits this one out with a thigh injury, so it will be interesting to see how new boy Jozo Simunovic gets on tonight.
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Celtic manager Ronny Deila
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"Everybody was disappointed not to get into the Champions League and it can take a bit of time to get over it.
"But I think we have cleared the air now and can focus on getting forward. We still have so much to look forward to. That is how you progress. You have good and bad experiences. You have to move on and learn. That's what I mean by clearing the air.
"I think we are on our way up. We were disappointed at the weekend, but this is another stage in the season.
"We have six fantastic games to play in the Europa League, and we want to get through the group."
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Celtic have won nine of their 13 matches this season but two defeats in the last three have left something of a cloud over manager Ronny Deila.
A 2-0 loss in Sweden saw the Glasgow club crash out of Champions League qualifying at the last hurdle and Saturday's 2-1 defeat at Aberdeen means they were knocked off the top of the Premiership table.
Jozo Simunovic makes his Celtic debut following a deadline day move from Dinamo Zagreb and Kris Commons is given a start.
There are four changes to the team that lost to Aberdeen on Saturday, with Emilio Izaguirre returning at left-back, while James Forrest joins Commons in an attacking midfield role.
The injured Charlie Mulgrew misses out, with Tyler Blackett, Tom Rogic and Gary Mackay-Steven dropping to the bench.
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Ajax v Celtic. It's a tie to whet the appetite, with both teams enjoying rich histories on the European stage.
Truth be told, they would rather be elsewhere, having been eliminated from the main event. Celtic are still smarting from a Champions League exit at the hands of Malmo, while the four-time champions of Europe were knocked out a round earlier by Rapid Vienna - conceding five goals over two legs.
But this is a great way to open the Europa League...
Live Reporting
Colin Moffat
All times stated are UK
Get involved
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Latest PostPost update
So, Celtic start their Europa League with a decent point away to Ajax but there will be a few what-ifs since Ronny Deila's men were looking comfortable at 2-1 before Emilio Izaguirre's red card.
We'll be back with more live action from the Scottish Premiership over the weekend. Goodnight and thanks for your company.
And more from Ronny Deila
"We are a team and we win and lose together. Emilio Izaguirre does not have a bad record for red cards and he was having a good game before the sending off. He was keeping their best player quiet."
More from Ronny Deila
"It was a very good delivery [for the second Ajax goal] but it's something we need to work on; we need to get to the ball first."
Celtic manager Ronny Deila
"We had a great attitude and I'm very proud of the boys. We had good control before the sending off. When we went to 10 men we were in trouble and I think a draw is okay."
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Former Celtic striker Scott McDonald on Sportsound
"Celtic were the better team after the interval and you were waiting for them to get a third goal on the break because Ajax were pushing so many bodies forward. Then came the red card and it changed everything."
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Former Celtic goalkeeper Pat Bonnar on Sportsound
"I don't know if this zonal thing is working for Celtic, they are giving away far too many goals from set-pieces. It's costing them every week and you can't dismiss that"
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It has to be remembered that Davy Klaassen did make a mess of two good opportunities for Ajax in the second half, while Arkadiusz Milik headed over from close range, so the home side will think a draw was the least they deserved.
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I'm sure Celtic fans would have taken a draw prior to kick-off but this was a great opportunity to get three points on the board in week one of the Europa League.
The Scottish champions have only won twice in their last 16 away days in Europe - and both of those came in Iceland.
Celtic manager Ronny Deila on BT Sport
"We have been through a tough period. This is a good start. Good defence and good organisation. The confidence will come. When we played 11 v 11, they didn't have too many chances."
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There was something of a shock in Group A's other match with Molde winning 3-1 away to Fenerbahce.
Join the debate at #bbcscotfootball
MBEHAN on Twitter: "Celtic pressing the self destruct button again, why wasn't a proper left back signed during transfer window, #bbcscotfootball"
Marco Silva: "Izaguirre, as always, ends up being a liability #bbcscotfootball"
Andrew Priestley: "Before kick-off Celtic would definitely have taken a draw away to Ajax to start, but at FT it's a disappointing result. #bbcscotfootball"
FULL-TIME
Ajax 2-2 Celtic
A point away from home against the Dutch league leaders doesn't sound too bad does it? But Celtic were looking comfortable at 2-1 before Emilio Izaguirre was sent packing for a second booking on 74 minutes.
Kris Commons made the difference for Celtic, setting up first-half goals for Nir Bitton and Mikael Lustig.
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We're into added time in stoppage time...
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Celtic are temporarily reduced to nine men as Nir Bitton limps off but he's not away for long and he's back in the thick of the action as the visitors dig in.
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Ajax pump the ball long into the penalty area and it lands up in the arms of Craig Gordon. Will Ajax get another chance in the remaining couple of minutes?
CLOSE!
The board goes up showing four minutes of stoppage-time just as Arkadiusz Milik heads over the top from close range.
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We're into the 89th minute now. Can 10-man Celtic hold on for what would be a very useful point?
Join the debate at #bbcscotfootball
Chris Williams on Twitter: "#bbcscotfootball What the hell did I just say about zonal marking?!!!!!! Doesn't work Ronny, stop doing it."
GOAL
Ajax 2-2 Celtic (Schone)
This guy loves a goal against Celtic... Having scored in both of the 2013 Champions League meetings, Lasse Schone has done it again to draw Ajax level. The Danish substitute powers in a dangerous free-kick from out on the left and everyone misses it, including an unconvincing Craig Gordon.
SUBSTITUTION
A depleted and tiring Celtic are now hanging on grimly, packing men along their 18 yard line as Kris Commons goes off to be replaced by defender Saidy Janko.
HITS THE WOODWORK
Craig Gordon is hesitant as Mitchell Dijks gets his head to a deep cross and the ball comes off the inside of the post. The Celtic goalkeeper redeems himself by clawing the loose ball away as a cluster of players throw themselves at it. A narrow escape for the visitors...
CLOSE!
Ajax really should be level as Davy Klaassen rises to meet the ball in a central position maybe 10 yards out but he skews and awkward header narrowly wide.
SUBSTITUTION
Ten-man Celtic also make a change and it's James Forrest who is sacrificed for Tyler Blackett, who will fill in for the prematurely departed Emilio Izaguirre.
SUBSTITUTION
Ajax swap a Dane for Dane as goalscorer Viktor Fischer is replaced by Lasse Schone, who scored in each of the 2013 meetings with Celtic.
RED CARD
A now Emilio Izaguirre is off! What was the full-back thinking of as he chopped the legs away from Anwar El Ghazi?
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Celtic pair Emilio Izguirre and Stefan Johansen, both on yellow cards, clatter into opponents in quick succession, drawing weak claims for further action from the home side.
SUBSTITUTION
Celtic are forced into a change as Mikael Lustig limps off and Efe Ambrose comes on to take over at right-back. The big Nigerian is involved right away as his uncertain touch forces Craig Gordon to look lively and come running to smother.
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Upset-o-clock in Group A's other match: Molde are now 3-1 up at Fenerbahce, with Martin Linnes scoring on 64 minutes.
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Celtic spring another counter-attack and Stefan Johansen cuts in from the right to try and find Kris Commons at the near post bit the pass is cut out by Thulani Serero. Leigh Griffiths then has a pop from distance, with Jasper Cillessen holding on to the skidding ball.
SUBSTITUTIONS
Ajax make a couple of changes, with Daley Sinkgraven and Amin Younes making way for Thulani Serero and Arkadiusz Milik.
Join the debate at #bbcscotfootball
John Everyman on Twitter: "In my view, Commons & Forrest are the 2 best players on the team & should be on the pitch in all but the rare circumstance #bbcscotfootball"
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Kris Commons chips a cute ball over the top of the Ajax defence for Leigh Griffiths to run on to. The angle is tight and the striker is stretching as he volleys into the side-netting.
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Tom English
BBC Scotland at the Amsterdam Arena
"Kris Commons underlying the madness of the decision to leave him on the bench at Aberdeen on Saturday. Two assists so far and every time he stands over a corner Ajax gulp hard. His deliveries are causing the home team huge trouble."
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Celtic defender Mikael Lustig gets his head to another Kris Commons corner but can only steer the ball wide. The home fans are growing more and more disgruntled.
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Molde take the lead against Fenerbahce again, with Mohammed Elyounoussi on target. It's 2-1 to the Norwegians now.
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Celtic cause more problems from a Kris Commons corner, with James Forrest having two shots blocked in the area.
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A few holes appear in the Celtic defence but the visitors are let off the hook as Davy Klaassen attempts a fancy flick when he had time and space to let fly with a shot from the edge of the box.
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The impressive Amsterdam ArenA is close to full but the home fans have been pretty quiet. Can Celtic keep it that way?
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Ajax exert some pressure and win a corner in unusual circumstances as goalkeeper Craig Gordon clips the heels of team-mate Emilio Izaguirre as he shapes to kick clear. The set-piece comes to nothing, sparing the Celtic duo any further embarrassment.
KICK-OFF
The second half is up and running. No changes in personnel for either side.
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The teams are back out. More of the same for Celtic, although they would make life easier for themselves if they improve their ball retention.
Join the debate at #bbcscotfootball
Andy Craig on Twitter: "Has Ronny Deila finally realised that Commons is our best player? 2 assists and hopefully more to come. #bbcscotfootball"
Andy adds: "Celtic are a different team with Commons playing. Best Celtic player by a country mile. Hope Ronny sees that from now on. #bbcscotfootball"
MBEHAN chips in: "Celtic so much better with Commons in the side countless goals & assists in the last few years #bbcscotfootball"
Post update
Kris Commons hasn't started too many games this season but the midfielder has made a huge contribution tonight, setting up both goals. Are Celtic a better team with the 32-year-old playing? Use #bbcscotfootball on Twitter to let me know what you think.
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Elsewhere in Group A, Molde's lead didn't last long, with Fenerbahce drawing level before half-time thanks to former Manchester United winger Nani.
HALF-TIME
Ajax 1-2 Celtic
That will do nicely for Celtic. The home side have had most of the ball but goals from Nir Bitton and Mikael Lustig have the visitors in front.
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Ajax are at sixes and sevens every time Celtic fire a delivery into the penalty area. Can Celtic bring Jan Vennegoor of Hesselink or Chris Sutton out of retirement for the second half? Those guys would have a field day against this home defence.
GOAL
Ajax 1-2 Celtic (Lustig)
Simple as you like. Kris Commons pings in a corner kick and Mikael Lustig attacks it well to nod the visitors back in front. Leigh Griffiths will be feeling a bit better about that miss.
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Lone striker Leigh Griffiths has not seen much of the ball this evening but he's just blown a great chance for Celtic!
James Forrest is allowed to scurry free from a throw-in and cuts the ball back for Griffiths right in front of goal about five yards out but the shot is hopelessly scuffed and is saved by Cillessen via a slight deflection off a defender.
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A bit of a surprise brewing in Turkey as Molde take the lead against Group A favourites Fenerbahce. Tommy Hoiland with the goal from the penalty spot.
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Tom English
BBC Scotland at the Amsterdam Arena
"Ajax growing into this game after Fischer's equaliser. Celtic can't keep the ball. Any time they get it, they give it away instantly. Asking for trouble against a decent, but beatable, side."
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Kris Commons swings the set-piece deep into the penalty area but it floats out of play, with Nir Bitton claiming that he was being held back by a defender.
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A bit of respite for Celtic as they make ground in the opposition half and Kris Commons is bundled over to win a free-kick. Get the big men up...
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Former Celtic goalkeeper Pat Bonnar on Sportsound
"Celtic are defending well enough in numbers but they are making a couple of passes then just kicking it clear and giving it away. Ajax are much more controlled in their passing."
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Celtic are giving the ball away too cheaply, with Stefan Johansen the culprit this time. Nemanja Gudelj strides forward to have a shot but is well off target with his effort.
GOAL
Ajax 1-1 Celtic (Fischer)
The Dutch side draw level with a lovely goal as Amin Younes drives forward and his pass is cleverly back-heeled by Davy Klaassen into the path of Viktor Fischer, who steers a precise shot low into the corner from the edge of the penalty box.
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PICK IT OUT!
Have a look at Nir Bitton's early goal for Celtic. It was a peach of a strike from the big Israel midfielder.
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Ajax are seeing more and more of the ball but Craig Gordon is yet to be seriously troubled. Amin Younes scuffs a shot in from the left and the Scotland international goalkeeper flops on it at his near post to eat up a few seconds.
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Nice footwork from Anwar El Ghazi as the Ajax midfielder drifts in along the byeline from the right but two defenders take the sting out of the shot and Dedryk Boyata completes the clearance with a firm header.
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A wee scare for the visitors as a pass from Davy Klaassen is cut out by Jozo Simunovic and, with Celtic keeper Craig Gordon going the other way, the ball drifts past the post by four or five feet. The resulting corner from Ajax is a stinker.
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The Ajax build-up has been ponderous so far, allowing Celtic to pack men behind the ball and cope comfortably.
GOAL
Ajax 0-1 Celtic (Bitton)
What a start for Celtic. The high-pressing works a treat as Stefan Johansen wins the ball deep in the Ajax half, Kris Commons then shuffles past an opponent and slips a pass through for Nir Bitton to arrow a low strike into the far corner.
The ball was bulging in the net before goalkeeper Jasper Cillessen could even move...
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Much better from Simunovic as he brushes Nemanja Gudelj off the ball to win possession. That could be an interesting Croatia - Serbia contest.
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Not a great first touch for Celtic new boy Jozo Simunovic as the big defender sprays a pass straight into touch...
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Ajax have not really got a recognised striker on the pitch but it looks like Davy Klaassen will play in the most advanced position.
KICK-OFF
A peep of the whistle from Italian referee Luca Banti and Celtic get the game started...
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Group A rivals Fenerbahce and Molde meet in Turkey tonight, so we'll keep you up to date with any goals in that one.
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The teams are in the tunnel. Celtic are kitted out in an extremely high-viz fluorescent yellow strip. Ajax in their famous white and red.
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These sides have played eight competitive matches, with Celtic leading the head-to-head with four wins to three. The last meeting was a Champions League group match in November 2013, with Lasse Schone scoring the only goal in Amsterdam to give Ajax three points.
The Danish midfielder, on the bench tonight, was on target in Glasgow that season too but only after James Forrest and Baram Kayal had netted for a home win.
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Celtic captain Scott Brown
[Talking last night] "We have let ourselves down recently and we have to just go on and show more willingness to win games and finish teams off.
"We know we can play better. We have to believe in ourselves a lot more.
"We have the players in the dressing room who can do it. We need a little bit of luck as well.
"Football is all about little details. I think if we get that one goal and get the second goal and go on, it builds confidence throughout the team and fans and they put trust in you."
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Tom English
BBC Scotland at the Amsterdam Arena
"Ajax team is remarkably young - two teenagers in the defence, only one player over the age of 23, average age 21.5. You can't win anything with kids. Hmmm."
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Of course, Ajax head coach Frank de Boer did spend some time in Scotland, playing 17 games for Rangers in season 2003-04. He was twice on the losing side at Celtic Park in that time.
This is what he said ahead of tonight's tie: "Both clubs also have a nice history, but that does not count anymore.
"Celtic are always the favourite in their own league, especially now Glasgow Rangers play in a lower league. We are also favourites as well, and are also required to play good football.
"Celtic can make it tricky for anyone. I am confident that we can win, but it will be difficult."
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GET INVOLVED
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Ajax finished a long way behind PSV Eindhoven in the Eredivisie last season, having won the previous four titles. Frank de Boer's men have made a good start this time and sit top with four wins and a draw from their first five outings.
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Motherwell striker Scott McDonald, formerly of Celtic, is on the BBC Radio Scotland team this evening and he wants to see Kris Commons in a central position behind striker Leigh Griffiths.
"I think Kris is strongest in the number 10 role and there is always the question of does he have the legs to do a job out wide in Europe," says the Australian.
LINE-UPS FROM THE AMSTERDAM ARENA
Ajax: Cillessen, Tete, Veltman, Riedewald, Dijks, Gudelj, Fischer, Sinkgraven, El Ghazi, Younes, Klaassen. Subs: Boer, Van Rhijn, van der Hoorn, Milik, Schone, Serero, Viergever.
Celtic: Gordon, Lustig, Simunovic, Boyata, Izaguirre, Johansen, Brown, Bitton, Forrest, Commons, Griffiths. Subs: Bailly, Blackett, Ambrose, Ciftci, Mackay-Steven, Rogic, Janko.
Referee: Luca Banti (Italy)
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The Celtic back four will be kept on their toes by a youthful Ajax side, with the Amsterdam club's famous academy continuing to churn out top talents.
Anwar El Ghazi and Daley Sinkgraven are fresh faces to look out for tonight.
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Much of the frustrated finger-pointing has been in the direction of Celtic's defence. The Scottish champions raced into a 2-0 lead at home to Malmo, eventually winning 3-2, before a disappointing display in the return leg, while Aberdeen were down to 10 men when they grabbed a late winner with a simple, high ball into the box.
Virgil van Dijk has been sold to Southampton, although he did not exactly cover himself in glory in those two games against Malmo, and Charlie Mulgrew sits this one out with a thigh injury, so it will be interesting to see how new boy Jozo Simunovic gets on tonight.
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Celtic manager Ronny Deila
"Everybody was disappointed not to get into the Champions League and it can take a bit of time to get over it.
"But I think we have cleared the air now and can focus on getting forward. We still have so much to look forward to. That is how you progress. You have good and bad experiences. You have to move on and learn. That's what I mean by clearing the air.
"I think we are on our way up. We were disappointed at the weekend, but this is another stage in the season.
"We have six fantastic games to play in the Europa League, and we want to get through the group."
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Celtic have won nine of their 13 matches this season but two defeats in the last three have left something of a cloud over manager Ronny Deila.
A 2-0 loss in Sweden saw the Glasgow club crash out of Champions League qualifying at the last hurdle and Saturday's 2-1 defeat at Aberdeen means they were knocked off the top of the Premiership table.
TEAM NEWS
Celtic XI: Gordon; Lustig, Boyata, Simunovic, Izaguirre; Brown, Bitton; Forrest, Johansen, Commons; Griffiths.
Jozo Simunovic makes his Celtic debut following a deadline day move from Dinamo Zagreb and Kris Commons is given a start.
There are four changes to the team that lost to Aberdeen on Saturday, with Emilio Izaguirre returning at left-back, while James Forrest joins Commons in an attacking midfield role.
The injured Charlie Mulgrew misses out, with Tyler Blackett, Tom Rogic and Gary Mackay-Steven dropping to the bench.
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Ajax v Celtic. It's a tie to whet the appetite, with both teams enjoying rich histories on the European stage.
Truth be told, they would rather be elsewhere, having been eliminated from the main event. Celtic are still smarting from a Champions League exit at the hands of Malmo, while the four-time champions of Europe were knocked out a round earlier by Rapid Vienna - conceding five goals over two legs.
But this is a great way to open the Europa League...