Harlequins director of rugby Conor O'Shea defended England prop Joe Marler after he appeared to kick Grenoble's Arnaud Heguy in the head during their European Challenge Cup semi-final.
Marler, 25, was making his first appearance since being given a two-match ban for calling Wales' Samson Lee a "gypsy boy" during the Six Nations.
But he could find himself in trouble again after appearing to kick out at Heguy during Harlequins' 30-6 win on Friday.
"It was not a boot, it was nowhere near a boot - it was a shin," O'Shea said afterwards.
Speaking to BT Sport immediately after the game, O'Shea said the incident was not worth a red card.
It was not spotted by referee John Lacey at the time.
"He is under the spotlight. It's first time I've seen it. It's always difficult but you have to control your emotions," O'Shea said.
"Things happen on the ground that people react to. Is it a red card? I don't think so.
"You can be sure there's stuff going on on the ground. I went up to him and the props and said, 'I don't know what you do in there but well done'. It's not a red card, it has to pass a red card test."