Leinster coach Michael Cheika admitted his players were "broken" despite edging Harlequins 6-5 in a thrilling Heineken Cup quarter-final at Twickenham Stoop.
Two Felipe Contepomi penalties were enough to set up an all-Irish last-four appointment with Munster at Croke Park with Leinster surviving a relentless Quins assault.
“That was a pretty tough game,” said Cheika. “The guys in that dressing room are broken because it was so physical.
“We had to do a lot of defending, especially in the second half. It was mental as well as physical pressure.
“We showed a lot of character to defend that lead being pinned down in our territory for so long.
“Maybe we didn’t show a lot of accuracy but there was a lot of character against a quality side.
“This is a tournament we really want to win. It will now be a massive challenge against the best team in Europe.”