Defending champions Clermont overcame a 14-point first half deficit to defeat Biarritz 27-17 on Friday and reach the French Top 14 semi-finals.

Clermont, who had endured 10 fruitless finals before their title breakthrough last season, will now face table-topping Toulouse in Marseille on May 27 for a place in the June 4 final at the Stade de France.

But five-time champions Biarritz, who had led 17-6 at the interval at a Marcel-Michelin Stadium where Clermont had not lost since November 2009, were left to rue a controversial second half where they were temporarily reduced to 14 men.

"Biarritz had a well-organised defence and they targeted our weak points," said Clermont coach Vern Cotter.

"But things were a little better in the second half. It was especially a question of heart and we have seen the true character and virtue of this team."

After Clermont full-back Anthony Flock and Biarritz veteran Dimitri Yachvili had exchanged penalties, it was the visitors who took an iron-grip on the play-off with two tries in the space of 10 minutes.

Winger Arnaud Mignardi charged at the stretched Clermont defence and when the ball ran loose, Yachvili was on hand to score.

Yachvili converted his try to make the score 10-3 which soon became 17-3 after 38 minutes.

Winger Julien Peyrelongue charged down a Brock James kick before sprinting 85 metres to score. The try needed the confirmation of the video referee before Yachvili again succeeded with the conversion.

Clermont then kept in touch when skipper Morgan Parra popped over as penalty on the stroke of half-time for a 6-17 scoreline.

The champions were then handed a lifeline after 56 minutes when Biarritz's English full-back Iain Balshaw was sin-binned.

Clermont made the most of the one-man advantage when James went over for a try which was converted by Parra to make the score 13-17.

The champions comfortably had the upper hand and were soon 27-17 ahead after adding two more tries in the space offive minutes through back row forward Alexandre Lapandry and winger Jeremy Malzieu.

Lapandry's try was controversial with a lengthy video referral again required after it appeared Marcelo Bosch may have got a hand under the ball.

Biarritz coach Laurent Rodriguez was frustrated the length of time it took to make a decision on the crucial Lapandry try.

"I think we broke all records in waiting for the decision. It was a bad moment," he said.

"I'd like to see the TV images again to see what happened and perhaps be in a better position to analyse it. When it takes so long to decide, it's a worry."

On Saturday, Castres host the surprise package of this season Montpellier, who put paid to Toulon's chances in their final match last Saturday.

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