Quins, playing in their first European quarter-final for over a decade, dominated the match but could not convert vast amounts of possession into points.

Leinster led through two Felipe Contepomi penalties and it was not until the 67th minute that Quins registered their first score with Mike Brown diving over.

Chris Malone missed the conversion and Nick Evans failed with a drop-goal one minute from time as Leinster scraped their way into an all-Irish semi-final against Munster.

"It's been a lovely journey but at the same time it's come to an end and we have to accept that," said Richards.

"It's never easy to get as far as we have done and not win but you have to accept it. We'll learn from this. There are no regrets.

"No one left the stadium with five minutes to go. We gave the spectators value for money and we'll continue to try to do that."

Leinster coach Michael Cheika admitted his side had been run ragged as they sought to deny Quins in an enthralling contest.

"That was a pretty tough game. The guys in that dressing room are broken because it was so physical," he said.

"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 and 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."