Wilkins feels Chelsea striker's top-level career would end if he moves to China.
Former Chelsea assistant manager Ray Wilkins says the Blues will need Diego Costa in order to win the Premier League title this season.
Antonio Conte's side are seven points clear at the top of the table after beating champions Leicester City 3-0 on Saturday, and Wilkins is convinced Chelsea can't win the league without Costa's services.
The former Manchester United midfielder told Sky Sports News HQ: "If they are going to win the Premier League they are going to need this guy. He has been in fantastic form. Last year the guy was almost a disgrace, this year he has just been superb. He causes havoc for everyone.
"This guy is scoring every type of goal this year, and if you ask any defender, they would say he is probably the toughest guy to play against.
"If it’s financial, and he wants to move to China, then I don’t quite understand it to be perfectly honest, because I think as a footballer, if you’re going to go to China, now at 28 years of age, you’re basically saying, like Oscar, your career is finished."
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