They go into the Thomond Park encounter, one-point behind the Blood and Golds, who lead the way in a wide-open pool, with just two-points separating top from bottom.
They will be without hooker Mike Sherry and second-row Donnacha Ryan, who is a reported target for Perpignan, is unlikely to feature. But head coach Rob Penney reckons his side are in control of their European fate and insists they must triumph at home.
"We're masters of our own destiny," said Penney. "We could have been better, but it could have been worse and we're still in the hunt.
"We have got to do a job at home, because otherwise there is no point in jumping on the plane to Perpignan if we don't do that job."
Perpignan prepared for the European showdown with a disappointing 30-23 Top14 loss to Clermont Auvergne. And their woes were compounded by a host of injuries to key players. Tight-head prop Giorgi Jgenti fractured his wrist, lock Romain Taofifénua picked up a knee injury, No.8 Luke Narraway suffered a bruised hip and South African flyer Wandile Mjekevu strained an ankle.
Perpignan will also be without former Munster centre Lifiemi Mafi, who missed out on a return to his old stomping ground after being red-carded against Gloucester in Round One. The big-hitting centre was banned for six weeks for a tip-tackle and will not be eligible to return until next week.
"I was pretty excited when I saw the draw, [I was] obviously looking forward to going back to Thomond Park as that's a place I hold dearly," said Mafi. "To go back and play in front of the people there would have been a big honour."
Perpignan will however have James Hook at their disposal. The Wales utility back has been in imperious form for the Catalan club this season and has racked up 33 points in the opening rounds of the Heineken Cup, including a full-house against Gloucester.
- Munster have won five of their seven Heineken Cup games against Perpignan.
- Munster won a competition-high 33 turnovers in the opening two rounds.
- Perpignan's Lifeimi Mafi was the only player to be sent off in the opening two rounds.