Norwich manager Chris Hughton backed the decision to send off Wes Brown during Saturday's 0-0 draw at Sunderland.
Referee Martin Atkinson showed Brown the red card in second half stoppage time for a challenge on Ricky van Wolfswinkel.
It was the second time the defender had been dismissed this season, although the first - for a challenge on Charlie Adam at Stoke last month - was rescinded on appeal, but this time Hughton felt the decision was fully merited.
"The sending off was a correct decision," he said.
"Wes Brown's challenge was reckless. It was a whole hearted game and both teams had a real go, but it was a shame because it wasn't that type of game."
Overall, Hughton felt satisfied with his side's performance and said he thought a draw was a fair reflection of the game.
"We showed grit and determination but a draw was a fair result," he said.
"I felt we were the team most likely to score. A clean sheet away from home is valuable and we need to maintain that going into the Christmas period.
"We were very disciplined right the way through. There's a fair bit of confidence in the team and we've picked up momentum.
"What's pleased me more than anything is we've had a couple of big defeats (5-1 to Liverpool and 7-0 to Manchester City) and on both occasions we've responded well so that shows character in the squad.
"Bad days can happy to anybody, it's how you learn from it and our responses to those defeats have been really good."