Number eight Nick Easter has warned Harelquins cannot let their Munster mauling de-rail their Premiership title defence.

Director of rugby Conor O'Shea's side were outmuscled and outclassed in Sunday's 18-12 Heineken Cup quarter final defeat to the Irishmen in front of a capacity 15,000 crowd at the Stoop.

The margin of Munster's win could have been more convincing than the scoreline suggested with the visitors dominating the second half as Quins struggled to gain a foothold in the game - particulary at the tackle area.

Quins have now lost five of their past seven games, a run that has seen them slip to fourth in the Premiershhip table with Bath visiting the Stoop on Saturday.

And Easter has challenged his teammates to bounce back by becoming a more physical force at the breakdown.

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"We've got to regroup. That is five losses out of our last seven in the Premiership and Heineken in the last few weeks. We are where we are," he said.

"We've got three massive games in the Premiership to come and we have got to set our stall out.

"We're not going to let our season unravel. We are still champions of England and are in a good positiion to defend that title.

"People have targeted the breakdown area all year. We've responded well, but it is an area we are going to have to look at.

"Sides know that if they stop us at the breakdown they stop our attacking game, which is very good.

"We were not urgent or clinical enough in getting that first and second guy to the breakdown. You need that if you are going to get quick ball and play our game.

"I think we might have paid the price for having quite an easy group. We haven't played many games in the Heineken Cup of the intensity needed.

"We just couldn't get our level up there. It is a very dark dressing room, but we will have to address that quickly."

Three Nick Evans penalties had given Quins a 9-6 advantage at the break, but opposite number Ronan O'Gara - who missed two kickable efforts in the first half - responded with a three penalty blitz of his own in the first 10 minutes of the second half to give his side a 15-9 advantage.

He added a fourth - his sixth successful kick of the afternoon - close to the hour mark and there was no way back for Quins, despite Evans adding another penalty.

"We didn't play the way we can play, but we weren't allowed to because Munster bossed the second half," said O'Shea.

"We never had any phases to hold the ball through and they won that breakdown in terms of us not being able to recycle that ball.

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"The better team won. That was nothing to do with the referee. If you win the collision then generally you recycle the ball.  We didn't win the collisions.

"We cannot allow everything we have given this season to drift away. We want to get in the top four and get the opportunity to defend our title.

"When the sun comes up tomorrow we need to make sure we are focused for Bath, secure our place in the top four, get ourselves in to a semi-final and see where we go from there."