Chelsea great Gianfranco Zola believes Tottenham's Harry Kane poses a threat to his former club's imperious Premier League form when the London rivals meet at Stamford Bridge on Saturday.
Antonio Conte's league leaders have won their past six top-flight matches without conceding a goal, while Spurs needed a late turnaround against West Ham last Saturday to end a run of four consecutive draws.
Kane's late brace sealed a 3-2 triumph at White Hart Lane and the England striker, who returned this month from seven weeks on the sidelines with an ankle injury, now boasts a remarkable record of 18 goals in 22 games against London opposition
"It's a team that is difficult to beat. It's a team that has, in my opinion, a good balance of the two faces - they can attack well, but also they can defend well," Zola, who was speaking at the official unveiling of William Hill's Chelsea shop on Fulham Broadway, told Omnisport.
"Probably they are not going through the best moment, but they still are a team that you need to perform well against to beat.
"Now they have Harry Kane back, who is a player that is very important to the economy of their game. This can certainly be a very positive thing for them, but, as I said, Chelsea is in a very positive moment."
Spurs are aiming to bounce back from a 2-1 loss at Monaco on Tuesday that ended their hopes of reaching the knockout stages of the Champions League, although the volatile nature of the Premier League means Zola does not feel Chelsea can be sure of continuing their stellar run.
"I am confident in a way, but not confident in another because we are talking about the Premier League which is at the moment one of the most unpredictable leagues in the world," he added.
"Anyone can beat anyone. I am confident Chelsea are in a good moment, they won six games in a row and deserved to win all of them.
"They look good and that makes me feel good, but the Premier League is tough so there will be a little bit of uncertainty.
"If Chelsea maintain the same standards they have a very good chance."
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