Mark Hughes fears Djibril Cisse's red card will affect Queens Park Rangers' survival after falling into the drop zone.
The striker made a rash decision when he attempted to go for the ball with a two-footed lunge on Sunderland substitute Fraizer Campbell during QPR's 3-1 defeat at the Stadium of Light.
It is the second time in his short spell at the Loftus Road club that the Frenchman has seen red and Hughes fears the 30-year-old's latest dismissal will only hinder QPR's hopes for survival as he is now due to miss a number of games.
"It was completely the wrong challenge to make. It's affected us greatly, obviously the likelihood is we'll lose him for a number of games now and we can ill afford to do that," Hughes told Sky Sports.
"There's nothing we can do about that. It affected the game and it'll affect us in the games we have left so we've just got to get on with it and the personnel that is available will be the ones to get us out of this situation."
He went on: "Given the way that we were playing I don't think that it would've changed the result of the game because we really needed to up our game and we were finding it very difficult to do that.
"The sending off just compromised our performance and summed up the way the game was going for us.
"It was a poor performance all round and we've just got to pick ourselves up and forget about this one and go again."
Prior to the match, all eyes were on skipper Joey Barton who was dropped to the bench after a poor midweek performance which saw him substituted against Liverpool.
Despite Barton seemingly making his feelings known about his dismay on Twitter, Hughes said the midfielder understood his decision.
"He didn't have the best of games on Wednesday, Jamie Mackie did exceptionally well and I felt he deserved a start today so that's why I picked him," said the Rangers chief.
"I spoke to Joey, he understood the situation and accepted the decision with complete grace as I would have expected him to because he is a good professional."
QPR's defeat to Sunderland meant they dropped into the relegation zone and, with Arsenal and Manchester United on the horizon, Hughes has urged his players to show their character and determination to claw themselves out of the bottom three.
"It's not easy, but maybe the manner of the performance against Liverpool when everybody expected us to be beaten - the fact that they were a top side - maybe that helped us to focus our minds better than we were able to today against a very accomplished Sunderland side," said Hughes.
"Going up against Arsenal and Manchester United, we're going to have to make sure we put a shift in and make sure that we can make better decisions than we did today.
"We've got enough talent and ability. We have just got to make sure that when there are key moments in the games, that we make the right decisions."