Antonio Conte admitted his disappointment after substitute Alvaro Morata was sent off for dissent during Chelsea's penalty shoot-out win over Norwich in the FA Cup third round on Wednesday night, 17 January.
The former Real Madrid player received a first yellow card for diving in the penalty area and, only seconds later, was sent off as he furiously complained.
The Chelsea striker's red card came only minutes after Pedro also received his marching orders for stopping a counter-attack, after also previously being booked for diving in the box.
Chelsea still went through to the next round after the penalty shoot-out despite going down to nine men.
However, when asked during the press conference whether he was disappointed with Morata and Pedro over their dismissals, Conte said, "For sure, I think I am not happy for the second yellow card to Morata.
"The first was for a doubtful situation, but I haven't seen it again. The second yellow card was for dissent. You must pay great attention at this moment of the game to stay calm and to make the best decision.
"If there is diving, it is right to give a yellow card. I don't want an advantage, especially if you know there is this system. If someone gives a punch or an elbow, you must also pay great attention."
Morata and Pedro's dismissals are a big blow for Conte with both Spanish forwards now set to miss the upcoming Premier League clash with Brighton on Saturday, 20 January.
The Chelsea boss made a number of changes in his starting line-up to face Norwich, with the trip to Brighton coming only four days before the second leg of the Carabao Cup semi-final against Arsenal.
Yet, Conte was forced to bring on Andres Christensen, N'Golo Kante, Eden Hazard and Morata late in the game to avoid a shock defeat to Norwich.
"Our performance was positive. Despite making many changes, we scored one goal and we created many chances to score the second goal. Instead, we conceded with 10 seconds to go," the Chelsea boss said when asked about whether he was concerned about the fatigue of his players ahead of the games against the Seagulls and Arsenal.
"Now, we have to play in two days against Brighton at 12.30. We have to try to recover very well. I hope we don't pay, also because my decision was clear: to try to go to the next round tonight and give a bit of rest to the other players.
"For sure, we have to face many problems, and also because Pedro and Morata are not able to play, but we want to try to get three points."