Former Chelsea assistant manager Gianfranco Zola concedes the emergence of Fikayo Tomori has surprised him.

Tomori, 21, has already made 15 appearances for the Blues this term, helping turn Frank Lampard's men into title contenders.

And Zola feels former Blues manager Maurizio Sarri - as well as himself - might have missed a trick.

He told the Evening Standard: "Tomori is one of the players. Last year we had him in the pre-season and we couldn't see all the qualities that he is showing now.

"That is a surprise and a big lesson for us and me personally as well. They are going beyond my expectations."

Zola added: "Mason Mount is not surprising me because I saw the videos of him playing in Holland and Derby. He needed to adapt but there was always a big potential.

"I'm not surprised about Tammy [Abraham]. When we had him he was a raw talent but I loved the attitude and positivity. They have all got a great attitude."