Harlequins head of rugby Paul Gustard branded Joe Marler's actions "absolutely ridiculous" after the prop was sin-binned in his side's 48-10 mauling at the hands of Sale.
Marler did not appear to be provoked when he put his elbow into the face of Sharks forward Jean-Luc Du Preez at the start of the second half and duly earned 10 minutes off the field.
Although the visitors held out while the England loosehead was in the sin-bin, it was symptomatic of an ill-disciplined performance by the Londoners as they eventually conceded six tries.
"I'm sure Joe will look at himself, it's absolutely ridiculous," Gustard said.
"There's no need for that. There was plenty of off-the-ball stuff from Sale and we've got to rise above it but Joe was the protagonist and there's just no place for that.
"It cost us an important player for 10 minutes and put the team under pressure again."
Gustard also criticised his side's whole display as Quins failed to secure the win which would have taken them into the top four ahead of the weekend's action.
He said: "It was very poor, we weren't good enough. We got beaten up, Sale were much more physical than we were and got on top at the set-piece.
"The only thing we can do is look at ourselves, regroup and address selection. We've got to find a way to win games.
"For all our possession we weren't able to manufacture a score. We didn't control the middle of the field very well and our discipline was poor."
Quins are in Heineken Champions Cup action over the next two weeks, travelling to Bath before hosting Clermont Auvergne.
Looking ahead to those matches, Gustard said: "I want to see people out there that have got character, I want people out there to show a bit of spirit and I need to see something more from my team because tonight was not an acceptable performance from a Harlequins team."
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