Former Premier League referee Dermot Gallagher told Sky Sports that UEFA's decision to stand down the match official is telling.
"I think the fact the VAR has been stood down speaks volumes. It's just not a penalty, is it?" he said.
"If that was given in the Premier League, the media would be on it for a month. It was incredible. And why it was incredible is that this guy is a top referee, there's no doubt about that. If you watch the game, he was faultless for 96, 97 minutes.
"He's then been alerted to something by someone else, which he hasn't given on-field - quite rightly. I really don't know what he's seen to change his mind on the screen."