Chelsea head coach Antonio Conte says it is “unfortunate” that Nemanja Matic is now a Manchester United player.
Matic played a key role in the Blues’ Premier League title success last season before being allowed to complete a £40m move to rivals United in the summer.
Chelsea will be reunited with their former midfielder when they visit Old Trafford on Nissan Super Sunday, live on Sky Sports Premier League, and Conte has expressed his regret at the Serbia international’s departure from Stamford Bridge.
“About this player I can talk only really well because he played with us last season,” said Conte.
Man Utd vs Chelsea
February 25, 2018, 2:00pm
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“I think he was one of the key players in winning the title.
“Now Matic, unfortunately, is playing for Manchester United. I wish for him the best. Not on Sunday, but in the future.”
Matic was a regular for Chelsea last year, making 35 league appearances and also helping the London club to the FA Cup final.
Conte said last summer that selling the player was a “big loss” for the champions, and asked why Matic was allowed to join a potential title rival, the Italian replied: “In the past we have already managed this topic.
“I don’t want to come back and speak about the past because I think it’s not important, not interesting for us.”
Matic has backed striker Romelu Lukaku to succeed at Old Trafford having failed to score against any of the Premier League's top eight this season for United.
In an exclusive interview with Sky Sports, Matic added: “I was there [at Chelsea] for three-and-a-half years and I gave my best for that club and now I’m at Manchester United. I will play against them and I will give my best for United.
“We are all excited because these are games we all like to play I expect an open game because we want to win, they want to win for sure and it will be very interesting for the supporters.”