Enzo Maresca described Rory Delap’s sending-off as “embarrassing” after the Chelsea striker was dismissed on his return to action.
The Blues secured a place in the Carabao Cup quarter-finals – where they will be away to League One side Cardiff City – by surviving a second-half Wolves fightback to win 4-3 at Molineux.
Goals from Andrey Santos, Tyrique George and Estevao put Maresca’s side in control and they appeared to be cruising into the last eight.
Delap, out since August with a hamstring injury, came on as a substitute shortly after Tolu Arokodare had pulled a goal back for Wolves.
David Moller Wolfe’s 73rd-minute goal then offered the home fans hope and Delap was ordered off in the 86th minute.
Delap, booked for fouling Yerson Mosquera, was given a second yellow card after needlessly barging into Emmanuel Agbadou.
Jamie Gittens made it 4-2 and Wolfe scored again less than two minutes later.
Delap’s red card was the sixth picked up by Chelsea in their past nine matches.
“It’s embarrassing when it’s a red card like today because it’s two yellow cards in five or 10 minutes,” head coach Maresca admitted, adding that Delap’s second yellow card came after a “stupid foul”.
“I think we can avoid that, so it’s not good. After the yellow card I told him four or five times to keep calm.
“But Liam is a player that when he’s on the pitch he’ll be playing the game and he struggles to realise and listen.”
A chaotic end to the tie was in stark contrast to a one-sided start in which Chelsea were two up within 15 minutes and three up by half-time.
Wolves were all over the place in the first half but the visitors were themselves unconvincing for much of the second.
“Very happy first half, very upset second half. This is the analysis and my personal view of the game,” said Maresca.
“In the first half we were very good and second half we were not doing the right things. Probably the first goal we conceded opened a bit the game and gave them the boost and energy to come back in the game.
“I think we can avoid all the goals we conceded and also we had a very stupid red card that is completely unnecessary.”
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