Prop Beno Obano was sent off as Bath were knocked out of the Investec Champions Cup by a 47-21 loss away to Leinster.
The Gallagher Premiership leaders will be playing Challenge Cup rugby come the spring after a seven-try defeat in Dublin, combined with Benetton’s surprise 32-25 win over La Rochelle, saw them slip to fifth place in Pool 2.
Leinster, who have finished runners-up in the Champions Cup in each of the past three seasons, progress to the last 16 as group winners with a 100 per cent record.
Bristol, meanwhile, crashed out of European competition completely after finishing bottom of the pool following an agonising 33-26 defeat to Clermont Auvergne earlier on Saturday.
Bath raced into a 14-0 lead inside eight minutes at the Aviva Stadium thanks to Finn Russell converting tries from number eight Alfie Barbeary and full-back Tom De Glanville.
Fixture
Investec Champions Cup
Leinster
Bath
Robbie Henshaw’s quickfire double and a score from captain Jack Conan then turned the match in the home side’s favour.
Yet Johann van Graan’s visitors hit back and were 21-19 ahead at the break following De Glanville’s second touchdown of the evening and a further two points from Scotland fly-half Russell.
Leinster took control in the second period after replacement RG Snyman and Garry Ringrose crossed, either side of Obano being dismissed for a second yellow card.
Scrum-half Jamison Gibson-Park broke clear to increase the advantage, before World Cup-winning Springbok Snyman powered over following a line-out to register the Irish province’s seventh try.
Replacement Ross Byrne slotted the extras on the final two scores to add to four successful conversions from starting fly-half Sam Prendergast.
Bath’s scoreless second half was compounded by news from Treviso, where Benetton overturned a six-point deficit in the final 20 minutes to upset Ronan O’Gara’s two-time winners and seize fourth spot.
Earlier, Clermont snatched success against Bristol in dramatic fashion.
Pat Lam’s Bears fought back to draw level through a penalty try and scores from Steven Luatua, Noah Heward and Kieran Marmion.
But Thomas Ceyte forced his way over for the French hosts in the sixth minute of overtime to settle the contest and, ultimately, end Bristol’s European campaign.
In Pool 3, Tom Seabrook scored a hat-trick as Northampton claimed top spot thanks to a thrilling 34-32 win over Munster.
Curtis Langdon and James Ramm also crossed for the hosts, while England fly-half Fin Smith kicked three conversions and a penalty.
Munster briefly led following Seabrook’s opening score following two tries from wing Calvin Nash.
But, despite Diarmuid Kilgallen claiming a second-half double and adding a conversion, in addition to 10 points from Jack Crowley, the Irish province remain second in the group following Seabrook’s standout display.
Bulls thrashed Stade Francais 48-7 in the other Pool 3 fixture.
