Wolves midfielder Karl Henry has apologised for his sending off against Aston Villa on Saturday, admitting it cost his side the game.
Henry was dismissed with 15 minutes remaining and with the scores locked at 2-2, before Robbie Keane won the derby 10 minutes later.
He was shown the red card after kicking Marc Albrighton in the mid-drift, after the Villa midfielder grabbed Henry's leg.
Mick McCarthy's men are embroiled in a relegation battle in the Premier League and Henry will now miss crucial games against Liverpool, Queens Park Rangers and West Bromwich Albion.
The 29-year-old has told the club's official website that he admits his frustrations got the better of him and he regrets his retaliation.
He explained: "It was frustrating as I was trying to get to the ball and he was holding onto my leg. I was trying to get to the ball and I just kicked out in frustration to try and get away.
"As soon as I did it, I thought, 'what have I done', because you can't react like that on a football pitch. Marc Albrighton made the most of it, but I know I shouldn't have done it.
"I hold my hands up - it was a bad error of judgement and a terrible reaction which you just can't do. Ultimately it has cost us.
"We weren't in front at the time, but were level and I left us with 10 men for the final 15 minutes which saw them go on and get the winning goal.
"I have apologised to the manager and the rest of the lads and would like to apologise to the fans as well, because it was really poor."
Albrighton has also spoken out since the incident and believes Henry's aggression was out-of-character.
He told Sky Sports News: "He just probably saw red, he lost his head a little bit, but he's probably a really nice guy off the pitch.
One of us
"I don't really know him, but he probably just lost his head and some things just come over you.
"I've not got a bruise to show for it, but it did hurt. A kick in the chest would hurt anybody.
"But we got the three points which is all we're concentrating on so it's good to get them."
Meanwhile, McCarthy has accepted Henry's apology and is looking forward to the midfielder returning to action.
He said: "He is still one of us. He's going to be missing for three games so he's going to be available for 13.
"I don't know too many people who haven't made mistakes in their life and he hasn't made many at this place in the last five-and-a-half years, that's for sure.
"He's apologies to the players and to me as well.
"There was no excuse for doing it, but he's one of our players and he's been brilliant for the club. So he's still part of it."