The 2007 Heineken Cup Rugby champions Wasps have been knocked out at the pool stage for the second successive season after going down to Castres 21-15.
The London side finished second in Pool Two behind Leinster, who secured a quarter-final away to Harlequins after beating Edinburgh 12-3 at home.
Holders Munster will play Ospreys at home after they beat French side Montauban 39-13 to qualify top of Pool One.
Bath and three-times champions Toulouse have both qualified from Pool Five after a 3-3 draw at a sodden Recreation Ground.
Leicester will host Bath in an all-English last eight encounter, while Toulouse travel to take on top seeds Cardiff in the remaining quarter-final.