Saturday's all-French semi-final represents the fifth time in nine years two French clubs have reached the last four. This is the first semi-final for Biarritz. Toulouse, champions in 1986 and 2003, are waiting on Test fly-half Frederic Michalak who undergoes a fitness test on his dodgy ankle on Saturday morning.
If he plays he will be at scrum-half alongside Yann Delaigue, who leaves for Castres next season after being edged down the pecking order by Michalak and injured France scrum-half Jean-Baptiste Elissalde.
If Michalak is ruled out third-choice scrum-half Sylvain Dupuy will play.
Elissalde tore a hamstring in the Six Nations win over Wales and will not be back until next season. Biarritz can count on Test halfbacks Dimitri Yachvili, man of the match in the Six Nations Grand Slam win over England, and Julien Peyrelongue, who stepped in when Michalak was injured in the Six Nations this term.
Biarritz coach Patrice Lagisquet says the match is evenly balanced. "You can't really draw up a game plan because they think so well on their feet. They've got such a strong experienced squad they know how to change if things aren't going their way," said the former Test wing.
"We think we have the side to beat them but just because we've done it once already in the championship this season doesn't make it any easier."
Biarritz will be counting on fit-again No 8 Thomas Lievremont and non-stop blind-side flanker Serge Betsen winning ball at the breakdown.
Their pack develops a powerful rolling maul which Toulouse will have to counter legally if they want to avoid giving Yachvili penalty kicks. But the Toulouse backs of Clement Poitrenaud, Vincent Clerc, Yannick Jauzion, Emile N'Tamack, playing his sixth European Cup semi-final, and Cedric Heymans carry lots of menace if gaps open in the Biarritz defence.
And Biarritz will be without injured Australian centres John Isaac and Marc Stcherbina who have been so good in defence this season.
Under 19 international Thibault Lacroix and Argentina Test centre Martin Gaitan are lined up to play.
Toulouse No 8 Christian Labit would have preferred to play English champions Wasps, who face Munster at Lansdowne Road on Sunday. "Biarritz know as much about us as we know about them. It doesn't always help. They have a good, old-fashioned pack and two or three match winners in the backs," he said. "It could be a classic."
Probable teams Biarritz Olympique: Nicolas Brusque, Philippe Bidabe, Martin Gaitan, Thibault Lacroix, Jimmy Marlu, Julien Peyrelongue, Dimitri Yachvili, Thomas Lievremont, Ovidiu Tonita, Serge Betsen, David Couzinet, Herve Manent, Denis Avril, Jean-Michel Gonzalez, Petru Vladimir Balan
Toulouse: Clement Poitrenaud, Vincent Clerc, Yannick Jauzion, Emile N'Tamack, Cedric Heymans, Yann Delaigue, Sylvain Dupuy or Frederic Michalak, Christian Labit, Finau Maka, Jean Bouihlou, Trevor Brennan, Fabien Pelous, Jean-Baptiste Poux, Yannick Bru, Patrice Collazo
Referee: Tony Spreadbury (ENG)
AFP - 2004
