A long-range effort by Peyrelongue from inside his own half didnt have the distance but Biarritz were beginning to look dangerous.
It was the French team who were having the better of the opening minutes, driving the ball forward and keeping the Blues in their own half in what was turning into a kicking contest.
The breakthrough came in the form of a Biarritz try when the Blues looked to attack. Ngwenya picked up a loose ball and showed his pace on the wing before Traile collected the pass to score. Peyrelongue added the conversion.
Ben Blair got the Blues on the scoreboard with a penalty but the Blues kicking out of hand was letting them down, not getting the distance or the accuracy they required. Biarritz nearly scored again when they broke down the left and it was only a last gasp tackle by Leigh Halfpenny that prevented Ngwenya touching down.
However, the Blues soon counter attacked and Biarritz looked in trouble on their own try-line only for Ngwenya to clear the threat.
Peyrelongue kicked a penalty to give the visitors a 10 - 3 lead after 30 minutes but the Blues looked to build a platform with a clever Nicky Robinson kick. Biarritz were then penalised for holding on in the ruck. The Blues chose to kick at goal and Blair slotted the penalty over.
A Blues lineout in the Biarritz twenty-two just before the break saw them build a platform for Robinson to drop a goal closing the gap on the men from the Basque country.
Half time Cardiff Blues 9 Biarritz Olympique 10
The Blues pressed early on which lead to Biarritz being penalised in a scrum and Blair slotted the ball over to give the Blues the lead for the first time in the match.
The Blues missed out on a great chance after a great break after Jason Spice split the defence, he drew his man but Andy Powell failed to gather the ball on the twenty two when there was no one between him and the try line.
The Blues won a free kick from the scrum and looked to spread the ball wide. At last they looked dangerous and Robinson opted for another drop goal which he converted.
The lead didnt last long; from a scrum inside the Blues half Peyrelongue gathered the pass and glided past the defence to score. Peyrelongue again converted to hand the lead back to the visitors.
The lead changed for the second time in a matter of minutes when from the kick off Biarritz where penalised and Blair struck another goal to make it 18-17.
A foul in the ruck on Deiniol Jones lead to the Blues being awarded a penalty on the halfway line. Halfpenny stepped up for the kick and was unlucky that he didnt quite having the distance and the ball sailed just went under the posts. It was a tense game with the neither side able to fully dominate.
In the 70th minute Blair slotted another penalty to give the Blues a 4 point lead and ensure a tense last 10 minutes. The Blues failed to clear from the kick off and to make matters even worse for the Blues faithful Maama Molitika was awarded a yellow card for fighting in the 75th minute. The Blues were in their own twenty two and Biarritz opted for the scrum. Tito did superbly to stop the attack and turned the ball over letting the Blues clear their lines and hang on for what could prove to be a crucial win.
Final Score Cardiff Blues 21 Biarritz Olympique 17
15 Ben Blair 14 Leigh Halfpenny (69off) 13 Jamie Robinson 12 Tom Shanklin 11 Gareth Thomas 10 Nicky Robinson 9 Jason Spice 8 Andy Powell 7 Martyn Williams 6 Maama Molitka 5 Paul Tito 4 Deiniol Jones 3 Gary Powell (65off) 2 Gareth Williams (65off) 1 Gethin Jenkins (65on) 16 Taufaau Filise (65on) 17 T Rhys Thomas 18 Scott Morgan 19 Robin Sowden Taylor 20 Darren Allinson 21 Ceri Sweeney 22 Tom James (69on)
Pen Blair x 4
DG Robinson x 2
Tries Traille x 1 Peyrelongue x 1
Pen Peyrolongue x 1
Con Peyrelongue x 2