The west London outfit are ten points clear of nearest rivals Spurs having lost just one game since the beginning of October.
He said: “I’m surprised how good they have been. I was expecting him (Antonio Conte) to have a strong impact because he had it at Juventus.
“I watched Juve quite a lot and I was studying his game. I didn’t know because no-one knows. I expected him to do great long term and it is a surprise they are 10 points clear.
Conte is a great manager, he done it at Juve, he done it with Italy. A brilliant manager, of course.
“It [the title race] is still very open. If they slip up, which you can in every game, other teams need to be ready.”