The Blues have beaten United on all three occasions at Stamford Bridge since Mourinho’s move to United following his December 2015 sacking by Chelsea and his appointment at Old Trafford six months later.

With Eden Hazard in sparkling form with seven goals in eight Premier League starts, United are predicted to try to stop unbeaten Chelsea from playing.

Maurizio Sarri says Chelsea must expected the unexpected against Manchester United (Adam Davy/PA Images)

Blues boss Sarri said: “We need to expect everything because we have to play against a very strong team, and usually a very strong team play very well in important matches.”

Sarri was not prepared to comment on Mourinho’s tactics, which are often perceived to be negative, especially in big games.

“The problem is not the way of football, if I like it or not,” Sarri added.

“The focus is he is able to win. He has won everything everywhere, so probably that means he is right.”

Chelsea’s only defeat this season came in the Community Shield to Manchester City, who lead the Blues and Liverpool on goal difference at the top of the Premier League.

Mourinho, meanwhile, is embattled at United, who are eighth after three losses in the opening eight games, a start Sarri downplayed as he argued United have the strongest playing squad in the top flight.

Sarri says tomorrow's opponents Manchester United are a very strong team who player by player may be the best in the league. #CHEMUN

— Chelsea FC (@ChelseaFC) October 19, 2018

“They are a very strong team. Maybe player by player they are the best team in the Premier League,” Sarri said.

“At the moment I think City is better like a team, but player by player they (United) are very, very strong.”

That may be interpreted as implied criticism of Mourinho, but Sarri was not about to emulate his predecessor, Antonio Conte, in igniting a public feud with the former Porto, Inter Milan and Real Madrid boss, who won three Premier League titles in two spells at Chelsea.

Sarri, who is yet to win a trophy in his management career, said: “You are talking about one of the best coaches in the world – and I’m not at the moment one of the best.

“I think he will be able to win also in the future. Because he is really one of the best.”

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