Bristol head coach Richard Hill:
"There were some good individual performances, some good tries, but we are disappointed to have lost.
"I will probably continue to rest the 17 that missed this game for next weekend's European Challenge Cup tie in Viadana before bringing out the big guns again for the return leg."
Bristol: Going; Robinson, Pritchard, Denney, Stanojevic; Hayes, Rauluni; Clarke, Nelson,Thompson; Williams, Hodge; Short, Morgan, Ward-Smith.
Replacements: Reay for Denney (50), Nicholls for Rauluni (50), Irish for A Clarke (60), N Clarke for Nelson (50), Teague for Thompson (50), Grieve for Morgan (60).
Not Used: Rospide.
Ospreys: Cashmore, Terblanche, A. Bishop, L. Davies, Mustoe, Connor, Roberts, James, B. Williams, Millward, Wyn Jones, Bateman, Bater, Tandy, Beech.
Replacements: Karauna for L Davies (22),
M. Jones for Connor (70), Spice for Roberts (65), Bennett for B Williams (54), Griffiths for Millward (49), Evans for Bateman (54), Thomas for Beech (65).
Att: 7,684
Ref: Bruce Robertson (Wales).