'When I get the clips from the analysts and there's Leinster coming up, it's a worse feeling in the gut'

French is such as romantic language that the word which perfectly describes Lyon's horror injury situation ahead of Sunday's Champions Cup match against Leinster is the very poetic 'hécatombe'.

It translates as 'carnage', or 'slaughter' - which is pretty much how having 14 unavailable first-team players must seem when you're preparing to face the four-time European champions who have won every game this season.

The injury situation explains why fullback Jean-Marcellin Buttin has been switched to 10 for the first and only time since Cardiff last year, and why Etienne Oosthuizen, who normally plays in the second row, has moved to the back row with engine room colleague Killian Geraci in a starting XV containing five locks, with another on the bench and only one specialist backrow

Thibault Regard, meanwhile, returns straight from injury to captain the side from centre.

Lock Felix Lambey, who was stood down for three months in October after picking up a third concussion in a 12-month period has been named on the bench. Another absentee, scrum-half Baptiste Couilloud may return in time for the final Champions Cup pool fixture at home to Northampton.

"It's pretty brutal," the Top 14 side's attack coach Kendrick Lynn said of the blood level on Lyon's infirmary floor. "But everyone gets hit pretty hard this time of year. This is real in-the-trenches time - just getting to the international break is key."

Fly-half Patricio Fernandez and centre Pierre-Louis Barassi, a poster boy for the new, young face of France, are the club's latest casualties, both injured in the hard-fought Top 14 win at Agen last weekend.

"We're are starting to get some guys back," Lynn said before Lyon flew to Dublin for Sunday's match. "But we're hit pretty bad in the loose forwards.

"Gill, Sobelo and Cretin have just been playing and playing and playing because we're so short in the back row. This week we can't keep playing all those guys, because if we lose one of them, we're really going to be in trouble.

"So we're going to be turning round some of our loosies. We're going to be using some second rowers who are capable of playing loosie - which we're want to see anyway - like Oosthuizen - who are capable and are athletes.

But, elsewhere, options are limited. "In some positions, we have no choice," Lynn said. "At first-five, we're tight. Jonathan Wisniewski has played a lot, and we've lost Patricio and Jean-Marc Doussain."

But he added there are no plans to recruit a medical joker. "We're going to try and get through this at 10. Jean-Marcellin Buttin can play 10. He's a very smart footballer. He's not played much there but he's intelligent and has the skillset."

A long injury list would be bad enough ahead of any match. But this is not just any match. This is a European match in Dublin against unbeaten already-qualified Leinster who are looking for a home quarter final and home-country advantage in the semi-finals.

"When I get the package of clips from the analysts and I see there's Leinster coming up, it's a worse feeling in the gut than it is when we're playing some other teams," Lynne joked.

Then he turned serious. "Our focus now isn't the Heineken Cup. Our focus is Top 14 and getting the train back on the rails and going how we want to go and where we want to be going.

"We're using these games, honestly, to prepare as best we can for what's coming afterwards.

"Leinster in Leinster - at the moment they're playing so well, especially at home. I almost felt that game where they came to the Matmut Gerland and just beat us really launched them. Since then they've just been punishing teams."

But, make no mistake, this is not a game that Lyon have written off. "We've got some key performance focuses that we can measure ourselves - internal measures that we can see after the game.

"Whatever the result, we can say, 'this is what we wanted to do, did we achieve it?', and then do it again next week but even better. We're just really taking away the result focus."

While the final result isn't the focus, pride is also at stake. "It's never nice to take a fair few - there is that in the back of your mind - but it's definitely less of a factor for us because we know it's going to be hard.

"Leinster spank a lot of teams, even ones who come full strength, and we're pretty hit with injuries and are going to need to turn over a few of our guys."

Europe has been something of a curse for Lyon this season. They got away to a flier, winning eight of their first nine in the Top 14. But their campaign has stalled since the Champions Cup kicked off. But they've been here before

"It's not a new thing for us," Lynn said. "We did the same thing the year before, and even a little bit the year before that.

"There always seems be this period where we get off to a flyer in the Top 14 - then Europe comes.

"We've been here before and we've gone through it again. So we've tapped into what we did last year in terms of how we got out of it. We're trying to strip things right back to basics.

"Instead of trying to add things in, trying to get too complicated, we're trying to remove as much as we can, as much noise - externally and within our play - to concentrate just on what we do real well.

"We hit that real tough period after Europe started. After we'd lost at Northampton and against Leinster, we went to Montpellier and got turned over really easily there - we had a really poor performance. We had a good hard look and said 'what do we do well, let's get back to doing that'.

The slump, in which they lost six of their following eight games, has given them something of a kick in the behind.

"Sometimes being in first place isn't that good for us, either," Lynne said. "It's really nice, but it does set in a little bit, that complacency.

"As much as you don't like to admit it, it's true. The guys were just a little less hungry. There's a great French word for it - exigence - it kind of covers not having that edge and the fact the were in first, that crept in."

That hunger is back. But Lynn didn't see it in the 50-pointer win over Bayonne at home a fortnight ago as much as he did in the single-point victory at Agen last weekend.

"It wasn't the prettiest game to watch - but, for us, that second half was probably meant more to the team and the club winning like that, hard, at Agen than putting 50 on Bayonne at home the week before

"The guys dug deep and got it done. Winning ugly like that can sometimes be a beautiful thing."

Prop Xavier Chiocci got the all-important score in the dying minutes to give Wisniewski a shot at goal from out wide for the lead.

But Lyon earlier had three touchdowns disallowed in a frantic 10-minute period. "At the time I was a little bit frustrated but I think in every one of the tries the referee had reason to turn them round," Lynn said, "but it's really good that the guys kept going after those setbacks of thinking you've scored but they get turned around but staying in the moment.

"They found a way to do it at the end, which was awesome. And Wisniewski came on and he's pretty cool at the moment, calm with his goalkicking, which was key - especially the one from the sidelines to get us in the lead.

"He's a pretty experienced campaigner. He's at that stage of his career, he's coming to the end but he's just really enjoying himself.

"He's got a really good mindset, very relaxed in the way he goes about things. He trains hard and prepares well - but it shows there in those situations where there's a lot of pressure, but he's in the right mindset, relaxed enough to perform under pressure."

Leinster :

Larmour - D Kearney, Ringrose, Henshaw, Lowe - Byrne, McGrath - Van der Flier, Deegan, Ruddock - Fardy (cap), Toner - Furlong, Tracy, Healy. Replacements: Cronin, Dooley, Porter, Molony, Doris, Gibson-Park, Frawley, R Kearney.

Lyon :

T  Arnold - Mignot, Dumortier, Regard (c), Nakaitaci - Buttin, Pélissié - Oosthuizen, Bruni, Geraci - Roodt, Rolland - Gomez Kodela, Alkhazashvili, Kaabèche. Replacements: Maurouard, Chaume, Yaméogo, Halaifonua, Lambey, Hidalgo-Clyne, Moura, Tuisova.