Wasps boss Ian McGeechan will insist the European champions retain a cup final mentality in Sunday's Adams Park clash against Llanelli Scarlets.
McGeechan's men will reclaim top spot in Pool Five if they beat the already-eliminated Welsh side.
And with current leaders Munster facing a tough appointment with Clermont Auvergne in France, Wasps know they cannot let the opportunity slip by.
Either way, the group could be decided by events in Limerick next Saturday when Wasps visit Munster, although Clermont cannot be discounted.
McGeechan said: "Because of the nature of this pool, every game is a cup final, and Sunday's game is no exception.
"We need a win to stay in the running for qualification to the quarter-finals.
"The quality of every team in this pool means we have to be wholly focused on producing a very high-quality performance, because Llanelli are a quality side who will come to Adams Park looking for a result."
Despite McGeechan's concern, Llanelli could struggle to match Wasps' power and pace.
The Scarlets are without Wales international half-backs Stephen Jones and Dwayne Peel, and they have yet to collect a point in this season's tournament following four successive defeats.
Wasps will be without Josh Lewsey, who is getting married this weekend, so Mark Van Gisbergen starts at full-back with centre Dominic Waldouck on the wing.
In the pack, England RBS 6 Nations squad members Phil Vickery, Tim Payne, Simon Shaw, James Haskell and Tom Rees all start, but Joe Worsley is on bench duty - subject to passing a fitness test - providing back-row cover for Haskell, Rees and Lawrence Dallaglio.
All Blacks wing Doug Howlett makes his Heineken Cup debut for Munster in a side captained by fly-half Ronan O'Gara, while Clermont include most of their big names, including centre Marius Joubert, hooker Mario Ledesma and flanker Julien Bonnaire.
In last night's action, Bristol retained an outside chance of quarter-final qualification despite a 19-11 away defeat against French champions Stade Francais.
They slipped to third spot in Pool Three as Stade found a cutting edge in the second half with tries from Ignacio Corleto and Julien Arias to emerge victorious.
Bristol now need to pick up five points from their final group game against leaders Cardiff Blues next Sunday, and hope Stade do not do the same from their clash against Harlequins, if they are to have any chance of finishing top.
"It's a tough one, but we aren't out of it," said Bristol head coach Richard Hill.
"We will give it one last go. If we get it right next weekend and get five points, it could be enough.
"We have a proud home record since losing to Leicester in the opening game of the season. We want to keep that record going, and we have high hopes."
Cardiff stayed on course for a last-eight spot by defeating Harlequins 23-12 at the Arms Park.
They now need victory over Bristol to guarantee Welsh representation in the knockout stages.
Blues head coach David Young said: "We now have a massive game against Bristol coming up.
"We are good enough to win there - but if Bristol are allowed to dictate the pace of the game we will have problems.
"We know how difficult it will be to go there and get a result - there are no easy games.
"All you can ask for going into the last game of the pool is that your destiny is in your own hands."
Tries in each half from centres Dafydd Hewitt and Tom Shanklin, plus 13 points from the boot of full-back Ben Blair, gave Cardiff their vital victory.
Ulster, meanwhile, gained a first win in Pool Two, fighting back from a 17-6 deficit to defeat Ravenhill visitors Bourgoin 25-24.
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