Now they have to hope Harlequins can do them a favour by beating Toulouse in France this weekend to keep alive their dreams of making it through to the last eight of the Heineken Cup again.
But even if that option is cut-off, they can still reach the quarter-finals of the re-structured Amlin Challenge Cup if they can win at the Twickenham Stoop. Their 36-19 home win over Sale Sharks moved them into second place in the Pool and ready to pounce if three-times winners Toulouse slip up in the final two rounds.
"It was a really professional performance from the players. They delivered a game that we had talked about and prepared for," said Blues coach Dai Young.
"We wanted to take them on physically up front and our driving line-out and scrum caused them problems. Now we have to hope Harlequins can do us a favour in Toulouse this weekend.
"All we can do now is concentrate on winning in London next week. If we can do that then we're still in with a chance of going through into a European quarter-final.
"If it is the Heineken Cup, then great. If it is the Amlin Challenge Cup, then we will give that a good crack as well."