Brian O’Driscoll’s side, containing five of Ireland’s Grand Slam heroes, were battered relentlessly but prevailed thanks to two penalties by Felipe Contepomi.

Points may have been at a premium - Leinster led 6-0 until the 66th minute - but it was a gripping contest played with brutal intensity.

The Irish province, semi-finalists on three previous occasions, moved through the gears in the third quarter but with 20 minutes to go Quins were back on the offensive.

England full-back Mike Brown dashed over but substitute fly-half Chris Malone, on for injured former All Black Nick Evans, missed the conversion.

Evans reappeared as a blood replacement for Tom Williams in a move that angered Leinster’s dug-out but the Kiwi failed with a late drop-goal attempt.