Under-fire Leinster head coach Matt O'Connor admits this weekend's clash with Bath will be a defining moment in the province's season.
Leinster have endured a difficult recent run, and have slipped out of the play-off places in the PRO12 as a result.
While they could still fight their way back into the top four, their best chance of success this season might come in the Champions Cup which starts up again on Saturday.
Leinster will host Bath in the last eight, after escaping a tricky pool featuring Wasps and Harlequins, as they look to build on their vast European pedigree.
"It certainly defines the season because it’s knockout rugby and you lose you are out of the competition," O'Connor told the Irish Examiner.
"We’ve worked hard through the pool stages and now it’s about taking that opportunity."