Two late tries from replacement Samiu Vahafolau saw Biarritz overhaul Glasgow 21-14 in their Heineken Cup Pool 4 clash at Parc des Sports Aquilera.

Glasgow plunged to earth with a thump as Biarritz came from behind to claim Heineken Cup revenge.

The Warriors arrived in the south of France brimming with confidence in the wake of their stunning triumph at Firhill.

But despite another stirring performance which kept their noses in front for almost the whole match, they were pipped at the post by two tries from substitute Samiu Vahafolau.

Glasgow could not have dreamed of a more inspiring start as they opened up an 11-point lead in the first quarter.

From the kick-off by Dan Parks, Biarritz were penalised for offside and as a result of backchat, Welsh referee Nigel Owens marched the hosts back a further 10 metres to make Parks' strike a formality.

The early blow was an alarm call for the French and they began to exert pressure through enterprising handling play and teasing positional kicks - however, Glasgow's defence was equal to the task of stemming the wave of raids.

And their stubbornness was rewarded after 18 minutes when Parks banged over another penalty.

Even better was to come for the Warriors almost immediately. Following a patient build-up, flanker John Barclay burst clear of a crowd of markers.

It was a straight race from 35 metres between him and and American speed merchant Takudzwa Ngwenya, who was making his representative debut for Biarritz.

Barclay found an extra gear to pounce for a remarkable try.

Brave tackling and clever marshalling by the Glasgow defence staved off a reply, but they were powerless to stop Damian Traille getting his team off the mark nine minutes before the break with a simple penalty.

Traille added two more strikes, with Parks slotting an opportunist drop-goal between times.

The pendulum started to swing against Glasgow with Owens awarding free-kicks to the French for a delayed line-out throw and then a crooked scrum feed.

Then came the moment that set up the tension-packed finale.

Va'a, who had re-entered the action, was yellow-carded for lashing out in retaliation.

Biarritz spurned the chance of three points and instead went for position in the corner in their bid for a try.

And their enterprise paid off as substitute Vahafolau plunged over for the score, goaled by Traille.

Vahafolau completed his last-gasp double after a Parks drop-goal attempt was blocked.

Biarritz (3) 21
Tries: Vahafolau (2)
Con: Traille
Pen: Traille (3)

Glasgow (11) 14
Try: Barclay
Pen: Parks (2)
Drop: Parks

Biarritz Olympique Pays Basque: N Brusque; T Ngwenya, P Bidabe, D Traille, B Thiery; J Peyrelongue, F Cibray; E Coetzee, B Noirot, D Avril, J Thion (capt), S Dellape, S Betsen, I Harinordoquy, J Cronje.

Replacements: B August, P Balan, T Hall, S Vahafolau, M Bosch, H Fa'afili, A Willemse.

Glasgow Warriors: B Stortoni; L Fa'atau, A Henderson, D Gibson, H O'Hare; D Parks (capt), S Pinder; J Va'a, F Thomson, M Low, A Newman, D Turner, K Brown, J Barclay, J Beattie.

Replacements: E Milligan, E Kalman, O Palepoi, J Eddie, C O'Young, S Barrow, G Morrison.

Referee: Nigel Owens (Wales)