Bordeaux-Begles scored three late tries to send Ulster crashing to defeat in their opening match of the European Champions Cup.
Ulster led for most of the match after Andrew Trimble’s 21st-minute try.
But Sebastien Taofifenua battled over to edge the French club ahead eight minutes from the end.
Ulster conceded a penalty try, with Sean Reidy sin-binned for tackling a man without the ball, before winger Blair Connor got the third score.
The pressure will now be on Ulster to beat Exeter in their next Pool 5 fixture on Saturday as another defeat would effectively end their hopes to making the quarter-finals.
They were under considerable pressure in the early stages and trailed to an early Ian Madigan penalty.
But skipper Trimble found a great angle to take Ruan Pienaar’s pass and charge through for the opening try midway through the first half.
Jackson converted and added a penalty to give Ulster a 10-3 interval advantage.
Madigan reduced the gap with a second penalty early in the second half and Lionel Beauxis and Jackson traded kicks to leave Ulster 13-9 up.
That is how it stayed until the 73rd minute when a home penalty into the corner set up a five-metre line-out and Taofifenua scored from the driving maul.
Bordeaux were then awarded a penalty try when Reidy’s early tackle denied replacement scrum-half Baptiste Serin a score and Beauxis slotted the conversion.
To rub salt in Ulster’s wounds, Brisbane-born winger Connor broke away for the home side’s third try seconds before the final whistle.
Bordeaux-Begles: J Buttin; A Ashley-Cooper, J Dubié, R Lonca, B Connor; I Madigan, Y Lesgourgues; J Poirot, C Maynadier, V Cobilas, J Marais, C Cazeaux, L Jones, H Chalmers, L Goujon.
Replacements: O Avei, S Taofifenua, M Clerc, T Palmer, M Tauleigne, B Serin, L Beauxis, M Talebulamaijaina.
Ulster: J Payne; A Trimble (capt), L Marshall, S Olding, C Gilroy; P Jackson, R Pienaar; A Warwick, R Best, A Ah You, A O’Connor, F van der Merwe, I Henderson, C Ross, S Reidy.
Replacements: R Herring, K McCall, R Kane, P Browne, R Wilson, P Marshall, J Stockdale, R Lyttle.
Article source: http://www.bbc.co.uk/sport/rugby-union/37654854