An early chance for St Johnstone to load the penalty box as Liam Craig stands over a free kick on the right. His delivery sails straight into the arms of the goalie.

James McFadden
Former Scotland forward on BBC Scotland

Away we go in Perth and Rijeka.

The St Johnstone fans are making a right old racket at McDiarmid Park!

Rangers now know they will face Armenian champions Alashkert for a place in the Europa League group stages.

Steven Gerrard's side dropped down from the Champions League qualifiers after a 4-2 aggregate defeat by Malmo.

Alashkert, who also started in the Champions League, beat Qairat Almaty of Kazakhstan 3-2 over two legs to reach the play-off round.

And here's what happens in the nightmare scenario...

Celtic drop into the Europa Conference League play-off against Tobol Kostanay or MSK Zilina.

St Johnstone drop into the Europa Conference League play-off against Vojvodina Novi Sad or LASK.

If Aberdeen and Hibs slip up, they're out of the picture altogether.

Here is what happens next if all of our teams get over tonight's hurdles...

Celtic will face Dutch side AZ Alkmaar in the Europa League play-off round.

St Johnstone will take on Danish side Randers in the Europa League play-off round.

Aberdeen will meet Azerbaijan side Qarabag in a Europa Conference League play-off.

Hibernian will meet PAOK of Greece or Ireland's Bohemians in a Europa Conference League play-off.

Hibs may be without Paul Hanlon and Christian Doidge but a notable omission from the Rijeka starting XI is Swiss international Josip Drmic.

The forward has scored 11 goals in his 24 appearances since joining on loan from Norwich but is absent from their squad tonight.

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Aberdeen boss Stephen Glass has recalled his big-hitters tonight as the Dons manager makes fives changes to the side that beat Livingston 2-1 on Sunday.

Out go Jack Gurr, Niall McGinn, Teddy Jenks, Jonny Hayes and Jay Emmanuel-Thomas.

Coming into the side are captain Scott Brown, Ross McCrorie, Lewis Ferguson, Christian Ramirez and Calvin Ramsay.

Looks like it might be a 3-5-2 formation for Glass' men this evening.

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Aberdeen: Lewis, McCrorie, Gallagher, Considine, Ramsay, McGeouch, Brown, Ferguson, MacKenzie, Hedges, Ramirez.

Substitutes: Woods, Ritchie, McGinn, Emmanuel-Thomas, Ojo, Hayes, McLennan, Jenks, Gurr, Campbell, Ruth, Hancock.

Breidablik: Einarsson, Atlason, Muminovic, Margeirsson, Svanthorsson, Einarsson, Sigurjonsson, Ingvarsson, Eyjolfsson, Vihjalmsson, Gunnlaugsson.

Substitutes: Bragason, Helgason, Sigurdarson, Margeirsson, Gudbjargarson, Steindorsson, Gislason, Yeoman, Robertsson, Jonsson, Thorsteinsson.

Celtic: Hart, Taylor, Welsh, Starfelt, Ralston, Rogic, McGregor, Turnbull, Forrest, Christie, Furuhashi

Substitutes: Barkas, Bain, Bitton, Ajeti, Soro, Edouard, Bolingoli, Urhoghide, Montgomery

Jablonec: Hanus, Krob, Zeleny, Kubista, Holik, Pilar, Povazanec, Houska, Plestil, Kratochvil, Dolezal

Substitutes: Vlastimil Hruby, Vajner, Surzyn, Stepanek, Martinec, Hubschman, Malinsky, Vanicek, Smejkal, Cvancara.

Celtic make just one change from the 6-0 trouncing of Dundee.

James Forrest returns to the starting line-up ahead of Liel Abada.

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Speedy winger Martin Boyle has made a blistering start to the season for Hibs, scoring five goals in the first five games.

Can he keep that run going tonight?

St Johnstone manager Callum Davidson explains that influential midfielder David Wotherspoon is missing since he is a close contact of a positive Covid case.

"For me it's a massive blow, he's such an important player," he says.

"We've got to keep the ball, we can't give it away tonight and David is one of our best players doing that.

"We need to make sure we have a really solid shape and I'd like to press them as high as we can but there's a danger that could expose us against quality players. Hopefully we can stay in the game right up to the end and give ourselves a chance."

St Johnstone are not regular European participants but they have faced Turkish opposition before, losing 3-1 on aggregate to Eskisehirspor in 2012-13 Europa League qualifying.

Saints fans have had a few good nights though, seeing off Hamburg in the early 70s and upsetting Rosenborg and Luzern this century.

There was also a thrilling 3-3 draw with a star-studded Monaco side in 1999. Unfortunately, the Ligue 1 visitors were defending a 3-0 lead.

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Of course, Hibs were the first British team to grace the continental stage as we know it after they were invited to play in the inaugural European Cup back in 1955-56.

Tonight marks their century of European appearances.

There have been some notable wins against the likes of Barcelona, Napoli, Porto and Sporting Lisbon along the way but if you're under 50 you won't remember any of those.

"We went into the first game with clear heads about what we wanted to do as a team and I think we produced a performance that reflected that," said Hibs boss Jack Ross yesterday.

"I think we have travelled here in the best possible frame of mind in terms of where players are performance-wise at the moment."

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"For a club like us, to be challenging against Galatasaray, who are probably one of the sort of powerhouses of Europe… It’s a big challenge, a huge game," said St Johnstone boss Callum Davidson yesterday.

"We’re delighted we managed to take them back to McDiarmid with a chance. The players are all buzzing, (I) just need to calm them down a little bit.

"European nights, under the floodlights at McDiarmid with a full house - I think all St Johnstone players, fans, myself, coaches, the hierarchy, it’s what we want, what we want to remember.

"We need to make sure we play against a team, rather than play the occasion, and that we’re focused right. If we do the right things and try to perform to a high level, it gives us a small chance to get through."

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As expected, captain Jason Kerr has recovered from a knock and returns to St Johnstone's defence. However, cup hero Shaun Rooney is on the bench with James Brown preferred at right wing-back.

David Wotherspoon doesn't make the squad, so in comes Murray Davidson in midfield.

Michael O'Halloran also returns to partner Chris Kane up top, with Glenn Middleton not eligible.

This looks like a tough assignment for Hibs but they can take heart from last week's first leg.

Jack Ross' side recovered well from losing a sucker punch goal, with Martin Boyle firing in the equaliser. However, it could have been a whole lot better since Lewis Stevenson thumped the post with a first-half shot and Dan Mackay messed up a golden one-on-one chance right at the death.

Rijeka, who make five changes from the first leg, and Hibs remain unbeaten at this early stage of the season, so both will be in confident mood.

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Callum Davidson completed a dream first season in management, steering St Johnstone to glory in both cups.

Can he complete another Roy of the Rovers storyline this evening and dump Galatasaray out?

His side briefly led against the 10-man Turks before securing a memorable draw in Istanbul.

Jason Kerr silenced the home crowd with 58th-minute penalty after goalkeeper Fernando Muslera had been sent off.

But the lead only lasted two minutes before Sacha Boey levelled.

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