Castres produced a strong showing on Friday to defeat Cardiff Blues 27-20 - but a late converted score saw the visitors leave with something.
The Welsh region team looked set to leave Stade Pierre Antoine empty-handed as they trailed 27-13 with the full-time whistle rapidly approaching.
However replacement prop Scott Andrews barged his way over from close range to claim Cardiff's second try, converted by Ceri Sweeney to clinch a late consolation point.
Castres stormed into a 27-6 half-time lead follow quick-fire tries from wings Vincent Inigo and Marc Andreu.
However Ma'ama Molitika sparked a second-half recovery that was capped by the late score.
Cardiff coach Dai Young would have left France satisfied with the bonus point considering his team were steamrollered in the opening half.
Castres were on the front foot from the start and opened the scoring thanks to a Romain Teulet penalty.
The full-back landed another two penalties either side of a Seremaia Bai drop-goal before Ben Blair struck with Cardiff's first points.
The goal-kicking full-backs exchanged further penalties to bring the score to 15-6.
But the French side landed a knock-out blow after 36 minutes when Vincent Inigo danced through the visitors' defence.
The wing pounced on a speculative Yoan Audrin kick after the bounce beat the visitors' defence and burst through the gap before skipping past the covering Leigh Halfpenny to score.
Teulet converted to give the side a 22-6 lead and things got even worse for Cardiff when Inigo's wing partner grabbed a try of his own minutes later.
Audrin was at the centre of the action again and burst down the Cardiff wing. The ball was spread wide to Teulet who chipped to the corner for Andreu to score, giving the hosts their commanding half-time lead.
But Cardiff sparked into life after the interval and played with an increased level of intensity.
They got their first reward six minutes into the second period when Molitika crashed over.
Wales centre Tom Shanklin re-gathered his own grubber and passed inside to Chris Czekaj who fed inside to substitute Tom James.
James was tackled high with the try line at his mercy but was able to recycle the ball.
Richie Rees popped to Tonga international Molitika who drove through two defenders to score. Sweeney converted to pull the Blues back to 27-13.
Cardiff had their tails up after the try and threatened to score on several opportunities.
In a dominant final 10 minutes Cardiff continued to push for a further try.
The score looked inevitable with minutes to go but the hosts killed the ball at the breakdown.
Thomas Sanchou was given his marching orders and Cardiff needed no second invitation. After a quick tap and several phases, Andrews drove his way through the Castres defence, with the help of Sam Warburton, to score the valuable try which Sweeney duly converted.
Tries: Inigo, Andreu
For Cardiff Blues:
Tries: Molitika, Andrews
Pen: Blair 2
Castres: 15 Romain Teulet, 14 Vincent Inigo, 13 Yoan Audrin, 12 Seremaia Bai, 11 Marc Andreu, 10 Cameron McIntyre, 9 Sébastien Tillous-Borde, 8 Chris Masoe, 7 Yannick Caballero, 6 Ibrahim Diarra, 5 Matthias Rolland, 4 Joe Tekori, 3 Luc Ducalcon, 2 Benjamin Kayser, 1 Yannick Forestier.
Replacements: 16 Mathieu Bonello, 17 Akvsenti Giorgadze, 18 Daniel Saayman, 19 Scott Murray, 20 Jannie Bornman, 21 Thomas Sanchou, 22 Pierre Bernard, 23 Pierre-Manuel Garcia.
Cardiff Blues: 15 Ben Blair, 14 Leigh Halfpenny, 13 Casey Laulala, 12 Tom Shanklin, 11 Chris Czekaj, 10 Ceri Sweeney, 9 Richie Rees, 8 Xavier Rush, 7 Sam Warburton, 6 Maama Molitika, 5 Deiniol Jones, 4 Bradley Davies, 3 Faao Filise, 2 T Rhys Thomas, 1 Gethin Jenkins.
Replacements: 16 Rhys Williams, 17 John Yapp, 18 Scott Andrews, 19 Paul Tito, 20 Andries Pretorius, 21 Lloyd WIlliams, 22 Dafydd Hewitt, 23 Tom James.
Referee: Alan Lewis (Ireland)