Chelsea boss Enzo Maresca offered no excuses after his side were beaten by Sunderland in injury time at Stamford Bridge.
Alejandro Garnocho put the Blues ahead in the fourth minute with his first goal for the club.
But Sunderland were level by the break and took all the points after snatching a late winner.
Maresca said: “When you lose a game like today it is not just about one player, we were not good enough in general and it is something we need to learn soon as the Premier League is full of these games.
“We started well with the ball but we were losing the second balls and against these sort of teams you have to know how to deal with that and overall we were not good enough.”
Maresca was also angered by his team’s poor defending for both Sunderland goals.
“It [the equaliser] was the first time they shot on goal. When they bring seven to eight players inside the box it is very difficult but it is something we need to do better,” he said.
“And we said many times that if you can’t win you shouldn’t lose. So we should have managed that better [the winner], but it is something to learn.”
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