Leicester boss Richard Cockerill's displease was evident after Saturday's Premiership loss to Harlequins, calling his team's defensive lapses "embarrassing."
Tigers have now won just one of their last five games in all competitions after crashing to a 23-16 defeat on home soil. The result was Harlequins' fourth win in six visits to Welford Road as Leicester slipped down to sixth in the standings.
Harlequins outscored their hosts two tries to one (a penalty try in the 80th minute) in a dominant display and Cockerill was furious with his players for slipping off far too many tackles.
"If people run at you and you don't tackle them they win, and that's what happened," said Cockerill.
"You have got to defend better than that, certainly in the first half. The sin-binning hurt us, they scored two tries in that period.
"But they ran hard and we did not get off the line and make our tackles. We let them play and they played very well and deserved to win. They wanted it more than us.
"We rallied well and that is great but you can't get yourself in that position in the first place.
"They outplayed us. I am not going to accept that, that is not good enough for us.
"Some of our defence early in the game was embarrassing. They will see it on Monday, and we have to be better."
Harlequins director of rugby Connor O'Shea reserved special praise for former England number eight Nick Easter, who played out of position at lock.
"How many times have I said that he will be younger by the time of the World Cup than Brad Thorn who won a World Cup winner's medal," said O'Shea.
"He is so competitive it is ridiculous. You can't write off someone like that, he will continue playing until he drops.
The Quins boss said it was crucial for his team to win the toss and make a good start in windy and wet condition.s
We talked about the opening two minutes. We wanted to play into the wind and when you do that you are forced to play," he explained.
"Chris Robshaw never wins the toss, Nick Easter has won the last two so he is going to do the toss every time now.
"We played that opening two minutes exceptionally well, it showed we could play our own game."