The team that led the regular Top 14 last season, and who only lost once at Stade Marcel Deflandre, physically dominated Ulster after a tense first half that saw the visitors hold their hosts to 13-10.

But once the teams changed ends, it was one-way traffic and La Rochelle ran in four tries to bag the bonus point and lay down a marker ahead of their back-to-back clashes with Wasps in December.

Having taken only three minutes to run in their first try at Harlequins in the opening round of games, La Rochelle were on the board after four minutes this time. Jeremy Sinzelle raced in from 40 metres after a long midfield pass from Ulster went to ground and was picked up by Ryan Lamb.

A brilliant wrap-around move involving Ulster's Australian international outside-half Christian Lealiifano gave Tommy Bowe room on the left wing and his inside pass allowed Lealiifano to cross for a try that he also converted. He then kicked a penalty to give Ulster a 10-7 lead after 15 minutes.

Two penalties in the second quarter by scrum-half Alexi Bales edged the home side into their narrow interval lead, and after that they made it a miserable afternoon for Ulster wing Andrew Trimble, who became his province's record most capped player with his 222nd appearance.

Ulster lost Lealiifano eight minutes into the second half and the first of the four tries run in by the home side in the final 40 minutes came when his replacement, John Cooney, cleared to the La Rochelle 10-metre line. But Cooney fatally missed touch and Victor Vito crossed as La Rochelle capitalised.

Three tries in the space of six minutes after the hour mark then demonstrated the dominance of the French side. Flanker Kevin Gourdon powered over from five metres, centre Pierre Aguillon was put in at the left corner by Vito and then the former All Blacks flanker sent skipper Jason Eaton over in the same corner on the narrow side of another ruck in the Ulster 22.

Bales converted the first of the three and then his replacement, Jean-Victor Goillot, added two superb touchline kicks to complete the home scoring. Ulster finished with a consolation try for Bowe, his 29th in the tournament, after he raced onto a chip through by Charles Piutau.