Chelsea manager Antonio Conte has bemoaned the poor discipline of his players after both Gary Cahill and Cesc Fabregas were sent off in Saturday's shock 3-2 defeat against Burnley.
The Blues found themselves 3-0 down at half time following a straight red for Cahill, before an improved second half performance saw the hosts come close to completing a comeback.
And Conte, while describing the performance as one of "two faces", has admitted that the increasing tendency of his side to go down to ten men is becoming a concern.
"We have to pay attention because you can see that in the last three official games, we finished twice with 10 men against Arsenal and today with nine men," he said, quoted by ESPN. "Also me, I have to study a new formation with 10 players online, because when it happens with this regularity you must be worried.
"After the red card we lost our composure and we conceded three goals. We have to improve a lot on this aspect because a situation of this type can happen, but we must pay attention to try to think that there is the rest of the game to try and do our best.
"Instead we conceded three goals and the second half was very difficult to change the result, despite the great commitment, the great desire, the great will of my players. I'm very proud for this but today I saw two faces: one positive in the second half and one negative in the first half."
Chelsea were without a number of key players, and the team selected by Conte highlighted the lack of depth currently in the squad.
But the Italian coach angrily dismissed suggestions that he played a weakened side in order to make a point over the need for new signings.
"Why? But why this question?" he said. "You are not satisfied with my starting XI? You don't know me very well.
"You can see that in our preseason, in every friendly game I played the best formation and it happened also today, because my choice was to put the players we have in this moment.
"I don't like this appetite for someone to send a message. Why do I have to send a message? Why? Why? I want to win. I want to win today. I wanted to win, not to send a message to my club. Why?"
He added: "I'm not worried. I'm not worried because we have to trust in our work and today there were three injured players, Pedro, Hazard, Bakayoko, and one player missing for a ban, [Victor] Moses.
"In the next game I don't know if Pedro is able to recover from his injury, but for sure we'll have two players out for a ban, Cahill and Fabregas. We'll find the right solution."