PARIS - Ulster beat Montpellier 27-16 on Friday but failed to grab a crucial fourth try which would have guaranteed them a European Cup rugby quarter-final place.
The Irish province racked up a fifth win in five Pool 5 matches to give them a seven-point lead over Leicester.
However, English giants Leicester should close the gap with a win at group whipping boys Treviso on Saturday (this morning Fiji time) before a potential pool decider at Welford Road against Ulster next weekend.
Ulster had looked in control, but never particularly comfortable in the first 40 minutes at Ravenhill against a Montpellier side who had lost six of their past seven matches.
Trailing 3-0 after a seventh-minute penalty from Eric Escande, Ulster were swiftly on top with two tries in three minutes.
Paddy Jackson's accurate cross-field kick was calmly collected by lock Robbie Diack to dive over for his third career try in the tournament.
South African halfback Ruan Pienaar kicked a difficult conversion from near the touchline for a 7-3 lead.
Pienaar added his team's second try on 26 minutes after collecting his own kick ahead.
His simple conversion made it 14-3 but Ulster eased off and ended up leading just 17-13 at the interval.
Montpellier lock Robins Tchale-Watchou burst through for 14-8 with Escande adding the extras.
Pienaar and Escande then exchanged penalties before halftime.
A penalty apiece followed early in the second half before former All Blacks prop John Afoa barrelled through for Ulster's third try just before the hour mark.
Pienaar added the conversion for a haul of 17 points but some dogged defence from Montpellier prevented Ulster grabbing the bonus-point try.
In the night's other match, Scarlets beat Racing Metro 19-13 in Pool 4, but neither side can make the last eight.
"It wasn't a great match," said Scarlets five-eighth Rhys Priestland who kicked 14 points.
"We put in a lot of hard work this season. We didn't have the precision required but we showed a lot of determination."