Chris Hughton was disappointed Manchester City's Kyle Walker was not sent off in the first half of Saturday's FA Cup semi-final as Brighton and Hove Albion were beaten 1-0 at Wembley.
Gabriel Jesus scored after just four minutes, but the tie might have turned in Brighton's favour had Walker been shown a red card before the interval.
The England full-back was involved in a heated confrontation with Alireza Jahanbakhsh and appeared to move his head towards the Brighton forward. VAR looked at the incident but did not recommend that referee Anthony Taylor upgraded a yellow card to red.
Having seen the replay, Hughton believed Walker should have been dismissed, suggesting other players have been sent off for similar incidents in the past.
"In my opinion, it was a red card," he told a news conference. "We ask players to be honest and Alireza doesn't make a big meal of it.
"If I look at the action, which I have done, there would have been numerous circumstances where that exact same action would have got somebody a red card. I think there was sufficient force in the action to warrant that."
On the use of VAR in the semi-final, Hughton added: "I think we're at the stage now where everybody is pushing for it. I'm probably one that has been converted a little bit. I'm still not sure how far it's going to take us.
"I'm even more disappointed that this was with VAR. Everybody will have a different opinion and I'm only giving you my opinion - I've seen it on three or four occasions."
Besides the first-half controversy, though, Hughton was proud of a Brighton display that might have been rewarded with something more tangible than City's plaudits had Aymeric Laporte not brilliantly cleared from in front of his own goal line.
"I know [City] had half-chances with the quality they've got, but I'm struggling to think of a clear chance - I don't think that has happened to them many times this season," he said.
"Particularly after going behind so early in the game, I can't imagine that there were too many in the stadium that didn't think that a second and a third was coming.
"We regrouped and came into what I thought - for our level and for what we are - was a really good game. We had chances. The majority of them were from set plays, but we were forceful enough to get them."