Perfectionist Antonio Conte has joked that man-of-the-match N'Golo Kante needs to cut out the mistakes.
Kante put in another commanding midfield performance in Monday night's 2-1 win at West Ham as Chelsea re-established their 10-point lead at the top of the Premier League.
He made 50 passes, of which just five did not find their intended target, as well as making the most tackles and winning possession more times than anyone in the Chelsea side.
But Blues boss Conte smiled: "He made five mistakes. He has to improve in this. He has to improve.
"I am joking. But I have to find one situation to tell him to improve. He's playing really well.
"He has great stamina, great quality and we are working to improve that quality. I'm pleased for him, but all my players performed very well."
Chelsea weathered a mild West Ham storm in the opening 25 minutes before Kante helped carve the hosts open in 10 seconds.
That was as long as it took for the Frenchman to intercept a loose pass near his own penalty area, and Eden Hazard to find the net in a lightning counter-attack.
Diego Costa grabbed the second from a corner five minutes into the second half, and Chelsea looked comfortable until Manuel Lanzini pulled one back in added time.
Yet even that consolation goal irked Conte, although he was delighted his players responded to weekend wins by nearest challengers Tottenham and Manchester City in kind.
"It's a pity to give away a second clean sheet at the end of the game, the second after Arsenal," added the Italian. "We must work a bit on this aspect.
"But I'm pleased for my players. It was not easy, to play after your opponents and know they won. If you drop points, you give hope to your opponents in the chase. We played under pressure and our answer was very good."