Chelsea striker Diego Costa has admitted that he arrived back at Chelsea for pre-season overweight.

The defending English champions have endured a torrid start to the season and Costa himself has come under fire for poor form and for his temperament. He was suspended for three games after altercations with Arsenal’s Laurent Koscielny and Gabriel, a sour event that also cost him his place in Vicente del Bosque’s Spain squad this month.

Costa has sought to take the heat off of under fire manager Jose Mourinho, suggesting the players must take responsibility for the team’s current slump. And Costa admitted his part in candid terms, “I’m going to be very honest: maybe a few weeks ago, five or six weeks ago, I was not on top of my game. At least physically. We talk within the players and we know that, maybe at the beginning, we were not 100% as we were supposed to be when we got here. I got injured at the end of last season and then I went on holiday.

“Maybe I got out of my diet and, when I came back, I was not the way I was supposed to be. I was a little bit overweight. That affected my game. You can be selfish and blame it on the manager but I’m not going to do that. I’m responsible 100%, and so are the other guys. So all we can do now is train very hard and work very hard to try to get back to that level where we were the season before.”

Costa, usually a taciturn figure in the media, suggested he was prepared to speak publicly for the squad, “I’m here because I’m happy with the manager but I’m not only speaking on my behalf. I am here to speak for everyone, for the group. All that matters at the end of the day is the group. Yes, he has supported me, but he has shown support for all of the players. I have spoken to all of the players and they all feel the same way about José. I don’t like giving interviews, but I’m speaking for the group. We all feel the same way about José.”