Hearts head coach Wouter Vrancken tells BBC Scotland: "I think the boys are doing well, we spoke a lot with some players about if they were ready and they all told me they’re good to go. Even when they are playing out of position, they’re all eager to help the team.

“We will stay with the four at the back, within the principles they know already and that they’ve done really well with. We have some young guys on the bench who might have to show themselves to help us at the end of the game, but hopefully we can start strong so we can find confidence and go from there.

"It would always be nice to start well, but it’s not that easy. I think they’re a good side because they’re energetic, they play with a lot of intensity and have the pitch they’re used to playing on.

“It’s not the best astro, it’s the worst I’ve ever seen.

"It feels like a home game [with all the Hearts fans] and you can see the fans are everywhere and I’m really happy with the support. Our fans are amazing and that helps the team."

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Malachi Fagan-Walcott say it's a "shock to the system" to be playing for Hearts in Europe, only two years since turning out for York City against Braintree Town in the National League.

Live moves fast.

The Spurs academy product did get a taste for European football during his younger days, but now he's living it.

"Growing up at the Tottenham academy, I've always had the luxury of watching European competitions," he said.

"To play in it is like a dream come true. For me, it's one of the biggest stages in football. This is the ultimate."

Cal Gilkison
BBC Sport Scotland

Oh Hyeon-gyu isn't the only familiar face Celtic will come up against.

Besiktas' visit also marks the return of former Rangers players Ridvan Yilmaz and Vaclav Cerny.

While ex-Celtic striker Oh is set for a warm welcome from the Parkhead crowd, Yilmaz and Cerny can expect anything but.

Cerny in particular could well face the ire of the home support, as the last time the Czech Republic winger played at Celtic Park he skooshed water at Celtic fans while celebrating Hamza Igamane's late winner in a 3-2 Rangers victory in March last year.

Besiktas' squad is littered with quality. Former Juventus striker Dusan Vlahovic and Leandro Trossard, a Premier League winner with Arsenal last season, are both key players.

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Martin O'Neill reckons Besiktas will be disappointed to be only sitting fourth in their domestic league but predicts they will be "a real handful" for Celtic, pointing out that striker Oh Hyeon-gyu might have "a point to prove" after an unsuccessful time at Parkhead.

The South Korea forward, who scored 12 times in 18 months in Glasgow but only started six times, later confirmed just that.

"I'm so excited - it's very special for me to be back here," Oh said. "It was sometimes hard for me, but Celtic became like my second home.

"Finally I am back here and I have to show them. Maybe I will be emotional if I score."

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It's been two years since Celtic beat RB Leipzig 3-1 in the Champions League.

That victory felt like a pretty significant moment for Brendan Rodgers' side in their European adventure that season, which ended in gut-wrenching fashion in Munich at the first knockout round.

What felt like a launchpad moment for the Parkhead club on the continent has turned out to be a false dawn, with their form in Europe in total regression since.

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Excluding qualifiers, Celtic have lost all of their past three major European matches.

Defeat tonight would mark four such straight losses in Europe for the first time since December 2017, all coming in the Champions League.

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Following the action in Thun, we'll turn our focus to Parkhead.

Martin O'Neill refused to put a ceiling on Celtic's European ambitions earlier this season, now he's wary of his side running out of games after just three matches of their Europa League campaign.

It has been a sorry story for the Scottish champions on the continent this term, collapsing at LASK in their bid for Champions League qualification before losing their first three Europa League fixtures.

Tonight's opponents Besiktas, in contrast, sit eighth in the 36-team table after beating Marseille and Hoffenheim, plus earning a draw with Crystal Palace.

"We need to get off the mark at some stage," said Celtic boss O'Neill.

"I was told that, statistically speaking, any team who's lost their first three games haven't made it through, so it doesn't augur brilliantly for us if that's the case.

"So if we go on for a fourth one then that would be a world record. We're definitely running out of matches, no question about it, but we are capable of still qualifying."

Thun are one of five teams without a Conference League point, having lost 1-0 away to Twente and by the same score at home to Hajduk Split.

Dubbed the 'Swiss Leicester' last term after a stunning league title triumph, they are showing signs of second-season syndrome but ended a five-game run without a win by staging a remarkable four-goal fightback to beat Lausanne-Sport 5-4 on Sunday.

This is the first time they have faced Scottish opposition.

Hearts, meanwhile, have played three games against Swiss opponents, beating Basel 2-1 away from home in the Uefa Cup group stage in 2004 but losing 2-1 away and 1-0 at home to FC Zurich in their Europa League play-off in 2022.

BBC Sounds

The Sportsound team are on the back shift to bring you coverage of tonight's action.

It all kicks off at 17:30 GMT, with live match commentary from Thun and Parkhead following.

Listen on this very page, or find BBC Radio Scotland Extra on BBC Sounds.

Calvin Miller and Tomas Magnusson have been added to Hearts' lengthy list of absences, and the injured pair are the only two players coming out of the side that started Sunday's derby defeat at Hampden.

Stuart Findlay comes in with Sabri Guendouz. With three centre-backs in the team, that could mean the Jambos line up with a back five.

But there are also suggestions that Stephen Kingsley and Jamie McCart will occupy the full-back positions in a back four, with Jordi Altena continuing in midfield.

On the face of it, the starting XI still looks pretty strong despite the ongoing injury crisis, although the bench looks severely depleted.

Young guns Matthew Gillies and Gus Stevenson have been called back from their loans at Stenhousemuir to help fill out the substitutes.

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Thun: Steffen, Dahler, Bamert, Burki, Mambwa, Reichmuth, Roth, Kait, Maier, Labeau, Dursun.

Substitutes: Spycher, Burgy, Zoukit, Kristal, Strannegard, Braschi, Derbaci, Christoffersson, Gutbub, Fehr, Ilic, Lengen.

Hearts: Reus, Altena, Fagan-Walcott, Findlay, McCart, Kingsley, Kerjota, Mendy, Guendouz, McPake, Braga.

Substitutes: Clark, Fulton, Williams, Kabore, Wilson, Pollock, Stevenson, Gillies.

Can we expect fireworks on another night of European action for our Scottish representatives?

There's been nothing sparkling about the respective Europa League and Conference League campaigns for Celtic and Hearts thus far, with both sides waiting for their first wins.

The Jambos are away to Swiss champions Thun in their search for a victory before Martin O'Neill's men attempt to brighten up what's been a gloomy season in Europe for his team.

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