Philippe Clement refused to criticise referee Kevin Clancy following Jose Cifuentes' red card against Dundee today.
The Ecuadorian midfielder was sent off following a VAR check after he could Dundee striker Amadou Bakayoko.
The former LAFC player was initially booked over the incident, however, after the intervention of VAR, Kevin Clancy opted to upgrade his decision to a red. Cifuentes did appear to catch the Dundee attacker high on the shin.
While Clement showed no anger over that decision, the Belgian did admit he was frustrated with Clancy over Todd Cantwell's disallowed goal during the first half. It was pulled back for a foul in the build-up, which meant the score stayed at 3-1.
"I never speak about a referee's performance because they make mistakes," Clement told BBC Sportsound. "We are on the training pitch every day to be our own referees, so are my assistants, so you cannot see everything.
"With the disallowed goal, I did not understand why the whistle was blown that fast. There was a clear view, so there was no foul, so it's better to let the play go on and then if there is a foul VAR can always come back to that.
"It was not necessary to kill the game in that way. For us, it's a big difference. For every team it's a big difference, scoring a goal or not. You put in a lot of hard work for that.
"That was a moment that for three seconds I was really angry about. I'm also a human being, and because of that I got a yellow card.
"I apologised to the referee after the game because I want to stay calm. That was a moment that I didn't understand."
More broadly on the game, the 49-year-old added: "I'm very pleased because whoever saw the match saw a winning team on the pitch, whoever is playing. Everybody is working hard for the time, to do the right things together, with and without the ball in the way that we want to play football.
"It's a deserved victory. Even with ten men, we created the best chances in the second half.
"You see the team is growing to become a team to have the right mentality. To do the right things together, and that's an important thing.
"No, it's not the best I've seen my team play. In the first half as a whole, we had some really good moments with the goals and other chances, but we also had some sloppy moments.
"Out of that comes this red card. Something we don't have to lose. We have to block it. Then we get the red card.
"Second half for sure, there was a lot of good team work but the boys have played in other games when the team work was also very good and have played good football."
Rangers now face a huge eight days in their season.
They play Real Betis in Seville on Thursday evening knowing they need a win to secure Europa League football after Christmas.
It's then all focus on next Sunday as Rangers make the short trip to Hampden to take on Aberdeen in the Viaplay Cup final.
Clement is happy that more players in his squad are showing they can step up to the mark.
He said: "I think more and more players are competing. Players coming in, like Dujon has in the last two games, to positions that are not his best positions, so you can see the right mentality there.
"We're going to need everybody on Thursday, on Sunday, and the weeks after. Everyone is speaking about those two games, but after that there's still a lot of games in the season.
"We're going to go really hard to get success in these two games because already it can be something really special in the season.
"After that, there are also really important weeks and months to come. We have to get the team ready so they're in the position where they understand what they have to do. In that way, it's getting better and better. I was really pleased with our discipline and the way that we attacked."
