Richard Hill believes his Bristol side are "pumped up" to give European Cup opponents Cardiff a chronic case of the blues on Sunday.
Despite losing twice in Pool Three - away to Cardiff Blues and Stade Francais - Bristol can still reach the quarter-finals.
They will probably need a bonus point victory at the Memorial Stadium to have any chance though - and also hope French champions Stade do not collect a five-point maximum from their away clash against Harlequins tomorrow.
Head coach Hill said: "We have still got a mathematical chance of going through, and the players are ready and all pumped up for it.
"We are the outsiders. I think Stade Francais and Cardiff are probably the favourites, but we could surprise everyone at the end, you never know.
"There is a huge incentive for us.
"We will need to concentrate and keep our discipline. We didn't do that at Cardiff (in November) and conceded three late tries.
"Cardiff keep going and going and wear you down. They will keep running the ball at you, and your defence has to be absolutely spot-on for 80 minutes."
Bristol, unbeaten at home in all competitions since mid-September, have called up wing Anthony Elliott after David Lemi flew home to New Zealand because of a family illness.
Changes in the pack see starts for prop Alex Clarke and flanker Alfie To'oala, but a star-studded Blues side will travel in confident mood, having beaten Bristol 34-18 during the opening round of pool fixtures.
As head coach Stuart Lancaster polishes the axe he will soon wield over his World Cup training squad, Exeter Chiefs coach Rob Baxter has backed Jack Nowell, Henry Slade and Luke Cowan-Dickie to be given a stay of execution.
Italy Under-20s held off a late Samoa blitz to retain their place in the World Rugby U20 Championship on Saturday and head coach Alessandro Troncon believes the experience will have served as a valuable lesson for his young troops.