Chelsea great Gianfranco Zola insists Juventus are capable of beating the European champions.
Chelsea meet Juve in their next Champions League group game.
Zola told La Gazzetta dello Sport: "The first performances were impressive. Chelsea are a real team. Against Tottenham they played a great game. In the first half they withstood the impact of their opponents, then in the second half changed gear and scored three goals. There is a lot of quality.
"(Thomas) Tuchel is flexible, intelligent, crafty. It has been understood since he took command of Chelsea. The match against Juve, however, is not a foregone conclusion. In the first half against Milan I saw signs of recovery. Juve never dies. It is also valid for the championship."