Scarlets face the daunting task of travelling to Clermont Auvergne on the opening weekend on the Heineken Cup.
Clermont have a formidable European record at Stade Marcel Michelin where they have not lost in three years, including their last 11 Heineken Cup matches.
The French giants, who were knocked out by eventual winners Leinster in a classic semi-final last April, sit third in the Top 14 standings having won six of their opening eight fixtures.
The Scarlets lie second in the PRO12 and have scored more tries than any other team in that competition with George North claiming an impressive five tries in as many matches.
Scarlets have never beaten Clermont.
The French side have made nine changes to the side that lost to Castres last week, recalling French internationals Aurelien Rougerie and Morgan Parra. Loose forward Gerhard Vosloo starts as he continues his comeback from injury.
Brock James is preferred to David Skrela at fly-half while Thomas Domingo, Benjamain Kayser and Davit Zirakashvili from a formidable front row.
Naipolioni Nalaga, Sitiveni Sivivatu and Lee Byrne feature in one of the most dangerous back three combinations in the competition.
Meanwhile, Head Coach Simon Easterby said the Scarlets are under no allusion as to the challenge ahead of them and said their game would have to be "close to perfect" to get a result.
"It doesn't get much tougher than travelling to Clermont; the history they have in their home ground is second to nobody and we are fully aware of the task ahead of us. There are 47 teams before us haven't been able to win there - so we respect them and what they do at home," he said.
"However, we also have to impose our game on them, as much as their back line is full of quality, ours is too and in terms of quality on paper we are fairly evenly matched.
"Clermont have such depth they have a couple of teams they can put out on the field that are capable of winning any game; they are very extremely well-drilled and very well-coached. It's a mark of a good team that they haven't hit their straps yet but they've been winning games. We know this one will be a target for them at home after losing out to Castres."
Easterby had a full squad to pick from for the big European opener, apart from this season's star wing performer Andy Fenby who is not available for selection after failing to return to fitness from a dead leg injury at last weekend's fixture.
The Scarlets draw on an impressive international clad back-line with seven Wales capped backs on duty; Rhys Priestland at fly-half, Tavis Knoyle at scrum-half, Jonathan Davies and Scott Williams in centre partnership, George North and Morgan Stoddart on the wings and Liam Williams at full-back.
Up front, the Scarlets put a new South African duo into the second-row with this season's signings Joe Snyman and George Earle combining for the first time. Impressive young Wales U20 tight head Samson Lee wins his place in the starting line-up after his man of the match performance last weekend against the Dragons alongside the very experienced front-row performers Matthew Rees at hooker and prop Phil John in an unchanged front-row.
ASM Clermont Auvergne: 15 Lee Byrne, 14 Sitiveni Sivivatu, 13 Aurelien Rougerie, 12 Wesley Fofana, 11 Naipolioni Nalaga, 10 Brock James, 9 Morgan Parra, 8 Damien Chouly, 7 Gerhard Vosloo, 6 Julien Bonnaire, 5 Nathan Hines, 4 Jamie Cudmore, 3 Davit Zirakashvili, 2 Benjamin Kayser, 1 Thomas Domingo.
Replacements: 16 Ti'i Paulo, 17 Vincent Debaty, 18 Daniel Kotze, 19 Julien Pierre, 20 Elvis Vermeulen, 21 Loic Jacquet, 21 Ludovic Radosavljevic, 22 David Skrela, 23 Benson Stanley.
Scarlets: 15 Liam Williams, 14 George North, 13 Jonathan Davies, 12 Scott Williams, 11 Morgan Stoddart, 10 Rhys Priestland, 9 Tavis Knoyle, 8 Rob McCusker (capt), 7 Josh Turnbull, 6 Aaron Shingler, 5 Johan Snyman, 4 George Earle, 3 Samson Lee, 2 Matthew Rees, 1 Phil John.
Replacements: 16 Ken Owens, 17 Shaun Hopkins, 18 Deacon Manu, 19 Sione Timani, 20 Kieran Murphy, 21 Gareth Davies, 22 Aled Thomas, 23 Gareth Maule.
Date: Saturday, October 13
Kick-off: 16:40 local (15:40 BST)
Venue: Stade Marcel Michelin
Referee: Peter Fitzgibbon (Ireland)
Assistant referees: Paul Haycock (Ireland), Simon McDowell (Ireland)
Television match official: Dermot Moloney (Ireland)
Timekeeper: Bruno Bessot (France)
Assessor: Claudio Giacomel (Italy)
Citing commissioner: John Cole (Ireland)