French Top 14 giants Racing 92 and Toulouse can clinch European Champions Cup quarter-final spots with victories over Irish opposition this weekend.
Racing, two-time runners up, host Munster in Pool 4 on Sunday while record four-time winners Toulouse head to Connacht in Pool 5 on Saturday in the penultimate round of the group stages.
Racing coach Laurent Labit says Munster boss John van Graan's men have an advantage as they were able to make 10 changes for last Friday’s Pro14 defeat at Ulster.
"When you see the team, you see the importance they put on that. Qualifying from their league (for next season), they'll do it," Labit said.
"They haven't got much to fight for and they prepare enormously for the Champions Cup," he added.
South African Van Graan will be without Ireland fly-half Joey Carbery who has been ruled out for up to four months with a wrist injury.
With Kiwi Tyler Bleyendaal sidelined due to a neck problem and experienced JJ Hanrahan a doubt for the trip to the French capital, Van Graan could be forced to turn to 20-year-old Ben Healy or centre Rory Scannell to wear the number 10 shirt.
"Ben has grown quite a lot over the last few weeks – he's been part of gameday warm-ups, he's been part of the squad and Rory has trained there," Van Graan said.
- Toulouse to 'freshen up' -
Unlike Labit's side, who are unbeaten in five games, last season's semi-finalists Toulouse have stumbled recently in the league, drawing at home to Toulon and losing convincingly at bottom-of-the-table Stade Francais on Sunday.
"For sure we have to change gear, freshen up, and start again in a better way," Toulouse back-rower Francois Cros said after the defeat in Paris.
"Certainly in the Top 14 we have tripped up but in the European Cup we have four wins so it's up to us not to tarnish those matches," Cros, who was named in France's Six Nations squad this week, added.
Another Top 14 outfit, Clermont, can take a step closer to the last eight by beating Ulster at Stade Marcel-Michelin on Saturday before travelling to Harlequins a week later.
"It's not a double or quits match. It's not going to knock us out in this pool but what we want is to qualify for a quarter-final, and quickly," coach Franck Azema said.
Elsewhere, reigning European champions Saracens, who are a point behind Munster in the standings, head to the Ospreys who are without a win in any competition since October.
Exeter Chiefs head to Glasgow looking to tie up a last-eight place, and Gloucester host Montpellier needing a victory to keep their hopes of progression alive.
Fixtures (all times GMT)
La Rochelle v Sale Sharks, Bath v Harlequins (both 19:45)
Clermont v Ulster, Ospreys v Saracens (both 13:00), Connacht v Toulouse, Glasgow Warriors v Exeter Chiefs (all 15:15), Gloucester v Montpellier (17:30)
Leinster v Lyon, Northampton Saints v Treviso (both 13:00), Racing 92 v Munster (15:15)
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