LONDON Holders Leinster ran in four tries to beat Exeter and keep alive their Heineken Cup hopes on Saturday but they face an anxious wait to see if they will qualify for the quarter-finals.
Fellow Irish side Ulster booked a place in the next round with a 9-8 win over French club Castres that put paid to Northampton's hopes of qualifying following their 27-20 reverse against Pool Four bottom club Glasgow.
Leinster came from 17-12 down at halftime to win 29-20 and finish second in Pool Five behind Clermont Auvergne who beat Llanelli 29-0 having already qualified for the knockout stages.
Leinster, who claimed a vital bonus point with tries from Gordon D'Arcy, Rob Kearney, Brian O'Driscoll and Jamie Heaslip, are hoping to finish as one of the two best runners-up.
Montpellier beat Pool Six winners Toulon 23-3 on Saturday to secure the first of two lucky-loser places, leaving all eyes on Munster's Pool One game against Racing Metro 92 on Sunday.
If Munster win and score at least four tries they can still pip their Irish rivals to the second runners-up place, providing pool leaders Saracens defeat winless Edinburgh to top the group.
"We are where we are," said Leinster head coach Joe Schmidt. "We can't control anything else that happens. There certainly won't be any celebrating from us because we know that Munster have a real target."
"That is one of the advantages of playing on the Sunday as they know clearly what they have to chase. They'll clearly work really hard and make sure that they get as close to that as possible against Racing.
"We knew how tough it was going to be to come here and get the five points, which was the minimum we required.
"I thought we were really good for it, and the quality of our tries was first rate, but I have a lot of respect for Exeter as well."
Ulster claimed their first ever win on French soil thanks to the boot of South Africa's Ruan Pienaar whose three penalties were enough to ensure they finished top of Pool Four.
In the process they extinguished Northampton's faint hopes of topping the group, while defeat for the English side at Glasgow ended their chances of qualifying as a runner-up.
Ben Foden's unconverted late try seemed to have secured a draw for Northampton before Peter Horne scored a fantastic individual last-gasp effort to register Glasgow's only win of the pool stage.
"To win these competitions you need to be more consistent," Northampton boss Jim Mallinder said. "We won three games and lost three games and that isn't good enough.
"We came up here to try and get to the quarter-finals of the Heineken Cup. We knew it was an outside chance, we needed four tries. We were close, but we weren't close enough."
Montpellier completed a surprise demolition of compatriots Toulon thanks to 18 points from half back Benoit Paillaugue.
A Jonny Wilkinson penalty put Toulon ahead before the hosts responded with a try from Thomas Combezou. Paillaugue then kicked three penalties and ran in a second-half try.
Pool Three winners Harlequins made it six wins from six on Friday as they beat Biarritz 16-9 in the driving rain with the visitors' Tom Guest scoring the game's only try.
Pool Two concludes on Sunday with a winner-takes-all clash between Leicester and leaders Toulouse.
(Reporting by Toby Davis; editing by Ken Ferris)