Now their first appearance in the Amlin offers them a route back to the Heineken Cup after a disappointing season in the Top 14.
And despite their domestic struggles, head coach Patrice Lagisquet is convinced his side will raise their game for their all-French Amlin affair with Brive at the Parcs des Sports Aguilera.
"Biarritz always play the European competitions at 100 per cent," said Lagisquet, whose team disposed of London Wasps in the last eight.
"The Heineken Cup games against the Ospreys and against Saracens this year were magnificent occasions. We won both those games at home and we only missed qualification for the quarter-finals of the Heineken because of a slip up in Treviso.
"I am convinced that this team has the potential to play in the Heineken Cup next season."
Biarritz warmed up for their clash with Brive with a hugely important home win against high-flying Racing Metro in the Top 14 last weeekend.
The 22-13 victory pushed Biarritz five points clear of the relegation zone with two league games remaining and assistant coach Serge Milhas was delighted with his team's display.
"The performance against Racing shows that this team has great spirit. We are not saved from relegation yet but it is close now," said Milhas.
"Sylvain Marconnet's excellent performance in the scrum was the perfect example of that spirit I mentioned.
"We beat a big team, a team who are in the running to win the Top 14 title. We beat them by playing good rugby and, with a little more confidence, we should be able to starting playing that kind of offensive rugby more often, putting together more phases of possession.
"We didn't allow Racing many opportunities to score, although they finally scored a try after we made a stupid mistake in defence. After that we had to start everything all over again to win the game.
"But with a great togetherness in defence and an excellent scrum we scored the points we needed step by step before finally scoring a try at the end of what was a beautiful game for us."