Matt Doherty hits Cristiano Ronaldo with a strong challenge in the centre circle. The Manchester United man wants a free-kick, but doesn't get it and rather gingerly makes his way to his feet.
Post update
Republic of Ireland 0-0 Portugal
Nothing to play for, for the hosts, but a brilliant atmosphere nevertheless.
Bruno Fernandes gets the game under way for Portugal. Here we go.
In the first match... Ronaldo late show and Republic heartbreak
Getty ImagesCopyright: Getty Images
In their first meeting in the group...
Cristiano Ronaldo headed two late goals to break the men's international goals record as Portugal snatched a dramatic 2-1 World Cup qualifier win over a luckless Republic of Ireland in Faro.
A famous Irish win seemed on as John Egan's header in first-half injury time kept them ahead until the 89th minute.
But Ronaldo levelled in the closing seconds of normal time before his winning header in the 96th minute.
Up until the incredible finale, it looked like being a miserable evening for Ronaldo after having a first-half penalty saved by young Republic of Ireland goalkeeper Gavin Bazunu.
However, the 36-year-old global superstar, continued to probe around the Republic's penalty area and after levelling, his winning goal broke the visitors' hearts.
Tonight's other action in Europe
Group A: Azerbaijan 1-3 Luxembourg, Republic of Ireland v Portugal.
Group B: Georgia 2-0 Sweden, Greece v Spain.
Group H: Russia 6-0 Cyprus, Malta v Croatia, Slovakia v Slovenia.
Group J: Armenia 0-5 North Macedonia, Germany v Liechtenstein, Romania v Iceland.
Germany and Denmark are the only countries to have qualified for Qatar 2022 so far, but they will be joined by Russia if 2018 World Cup runners-up Croatia fail to beat Malta.
That could be a hugely costly defeat for Sweden as they will lose top spot in Group B if Spain win in Greece.
How it stands
There's already been one match in Group A today with Luxembourg winning 3-1 in Azerbaijan, who had Tellur Mutallimov sent off after only 21 minutes.
That means the Republic will definitely finish below Luxembourg if they fail to win tonight. Stephen Kenny's side end their campaign away in Luxembourg on Sunday.
But this match is a huge one for Portugal as a win would take them two points clear of Serbia, who they face on Sunday in a group decider, with only the group winners guaranteed their places at Qatar 2022.
.Copyright: .
Dream debut for Gordon
What a start to life with England Under 21s for Everton's Anthony Gordon.
Two goals for the midfielder inside the first 11 minutes of his debut.
The young Lions lead Czech Republic 3-0 in a crucial Euro qualifier.
'We are evolving as a team'
Republic of Ireland v Portugal (19:45 GMT)
Republic of Ireland boss Stephen Kenny said: "You can see the improvement, but we have to work on a lot of other stuff. We have been doing that over the last few games and hopefully we can put in the performance that we need.
"Portugal are a world-class team - they're the previous European champions, Nations League holders, we know they've got a lot of players who have played in the Champions League final and so forth.
"[But] we are at home, we have a lot of good players ourselves and we are evolving as a team. You see the progression of the team and see the team evolving in front of your eyes every game we play."
It's going to be a capacity crowd tonight with a crowd of 52,000 at the magnificent Aviva Stadium.
Getty ImagesCopyright: Getty Images
Get Involved #bbcfootball
Your thoughts on the Republic's campaign and Stephen Kenny as manager
As always we welcome your comments throughout the evening so let us know your thoughts on this match, the Republic's campaign overall and your thoughts on the leadership of Stephen Kenny.
He has a contract until next summer, but should it be extended? Why? Why not? If you say no, who should replace him and why?
Tweet us using #bbcfootball and we will post the best messages in this page throughout the evening.
Getty ImagesCopyright: Getty Images
Post update
It's a big landmark today for defender Shane Duffy, who reaches his half century of international appearances.
Here is the side named by Stephen Kenny. Norwich City full-back Andrew Omobamidele misses out because of an Achilles injury, but that means a return for captain Seamus Coleman in what is expected to be a back three, with Matt Doherty and Enda Stevens wing-backs.
As expected, Manchester City midfielder Bernardo Silva misses out as he is being rested for Portugal's vital match against Serbia on Sunday.
Manchester United trio Diogo Dalot, Bruno Fernandes and Cristiano Ronaldo are among their starting 11 with a host of Premier League players on the bench - including Wolves trio Jose Sa, Joao Moutinho and Ruben Neves, Manchester City pair Ruben Dias and Joao Cancelo and Liverpool forward Diogo Jota.
Hello and welcome along to BBC Sport's coverage of the World Cup qualifier between the Republic of Ireland and Portugal.
I'm Michael Emons and will be talking you through the action tonight, with kick-off at 19:45 GMT.
Let's start off with seeing some team news.
All to play for...for Portugal
It's been a World Cup qualifying campaign to forget for the Republic of Ireland, as they can no longer make it to Qatar 2022, but their opponents Portugal still have it all to play for as they look to move closer to securing their spot in the Middle East next year.
Live Reporting
Michael Emons
All times stated are UK
Post update
Republic of Ireland 0-0 Portugal
Matt Doherty hits Cristiano Ronaldo with a strong challenge in the centre circle. The Manchester United man wants a free-kick, but doesn't get it and rather gingerly makes his way to his feet.
Post update
Republic of Ireland 0-0 Portugal
Nothing to play for, for the hosts, but a brilliant atmosphere nevertheless.
KICK-OFF
Republic of Ireland 0-0 Portugal
Bruno Fernandes gets the game under way for Portugal. Here we go.
In the first match... Ronaldo late show and Republic heartbreak
In their first meeting in the group...
Cristiano Ronaldo headed two late goals to break the men's international goals record as Portugal snatched a dramatic 2-1 World Cup qualifier win over a luckless Republic of Ireland in Faro.
A famous Irish win seemed on as John Egan's header in first-half injury time kept them ahead until the 89th minute.
But Ronaldo levelled in the closing seconds of normal time before his winning header in the 96th minute.
Up until the incredible finale, it looked like being a miserable evening for Ronaldo after having a first-half penalty saved by young Republic of Ireland goalkeeper Gavin Bazunu.
However, the 36-year-old global superstar, continued to probe around the Republic's penalty area and after levelling, his winning goal broke the visitors' hearts.
Tonight's other action in Europe
Group A: Azerbaijan 1-3 Luxembourg, Republic of Ireland v Portugal.
Group B: Georgia 2-0 Sweden, Greece v Spain.
Group H: Russia 6-0 Cyprus, Malta v Croatia, Slovakia v Slovenia.
Group J: Armenia 0-5 North Macedonia, Germany v Liechtenstein, Romania v Iceland.
Germany and Denmark are the only countries to have qualified for Qatar 2022 so far, but they will be joined by Russia if 2018 World Cup runners-up Croatia fail to beat Malta.
That could be a hugely costly defeat for Sweden as they will lose top spot in Group B if Spain win in Greece.
How it stands
There's already been one match in Group A today with Luxembourg winning 3-1 in Azerbaijan, who had Tellur Mutallimov sent off after only 21 minutes.
That means the Republic will definitely finish below Luxembourg if they fail to win tonight. Stephen Kenny's side end their campaign away in Luxembourg on Sunday.
But this match is a huge one for Portugal as a win would take them two points clear of Serbia, who they face on Sunday in a group decider, with only the group winners guaranteed their places at Qatar 2022.
Dream debut for Gordon
What a start to life with England Under 21s for Everton's Anthony Gordon.
Two goals for the midfielder inside the first 11 minutes of his debut.
The young Lions lead Czech Republic 3-0 in a crucial Euro qualifier.
'We are evolving as a team'
Republic of Ireland v Portugal (19:45 GMT)
Republic of Ireland boss Stephen Kenny said: "You can see the improvement, but we have to work on a lot of other stuff. We have been doing that over the last few games and hopefully we can put in the performance that we need.
"Portugal are a world-class team - they're the previous European champions, Nations League holders, we know they've got a lot of players who have played in the Champions League final and so forth.
"[But] we are at home, we have a lot of good players ourselves and we are evolving as a team. You see the progression of the team and see the team evolving in front of your eyes every game we play."
Meeting the public
Republic of Ireland v Portugal (19:45 GMT)
Looking good
It's going to be a capacity crowd tonight with a crowd of 52,000 at the magnificent Aviva Stadium.
Get Involved #bbcfootball
Your thoughts on the Republic's campaign and Stephen Kenny as manager
As always we welcome your comments throughout the evening so let us know your thoughts on this match, the Republic's campaign overall and your thoughts on the leadership of Stephen Kenny.
He has a contract until next summer, but should it be extended? Why? Why not? If you say no, who should replace him and why?
Tweet us using #bbcfootball and we will post the best messages in this page throughout the evening.
Post update
It's a big landmark today for defender Shane Duffy, who reaches his half century of international appearances.
Team news
Republic of Ireland v Portugal (19:45 GMT)
Here is the side named by Stephen Kenny. Norwich City full-back Andrew Omobamidele misses out because of an Achilles injury, but that means a return for captain Seamus Coleman in what is expected to be a back three, with Matt Doherty and Enda Stevens wing-backs.
Republic of Ireland: Bazunu, Coleman, Duffy, Egan, Stevens, Cullen, Hendrick, Doherty, McGrath, Ogbene, Robinson.
Subs: Kelleher, Travers, Hourihane, Idah, McClean, Collins, Browne, Parrott, Knight, Keane, Manning, O'Dowda.
As expected, Manchester City midfielder Bernardo Silva misses out as he is being rested for Portugal's vital match against Serbia on Sunday.
Manchester United trio Diogo Dalot, Bruno Fernandes and Cristiano Ronaldo are among their starting 11 with a host of Premier League players on the bench - including Wolves trio Jose Sa, Joao Moutinho and Ruben Neves, Manchester City pair Ruben Dias and Joao Cancelo and Liverpool forward Diogo Jota.
Portugal: Patricio, Semedo, Pepe, Danilo, Dalot, Palhinha, Nunes, Fernandes, Guedes, Ronaldo, A Silva.
Subs: Sa, Costa, Dias, Fonte, Cancelo, Moutinho, Carvalho, Sanches, Neves, Leao, Jota, Felix.
Thanks for joining us
Hello and welcome along to BBC Sport's coverage of the World Cup qualifier between the Republic of Ireland and Portugal.
I'm Michael Emons and will be talking you through the action tonight, with kick-off at 19:45 GMT.
Let's start off with seeing some team news.
All to play for...for Portugal
It's been a World Cup qualifying campaign to forget for the Republic of Ireland, as they can no longer make it to Qatar 2022, but their opponents Portugal still have it all to play for as they look to move closer to securing their spot in the Middle East next year.