Diego Costa could be on his way to Chelsea (Picture: Getty)

Jose Mourinho has kept his cards close to his chest over reports Diego Costa’s prospective move to Chelsea is a ‘done deal’.

The Atletico Madrid striker, who helped knock the Blues out of the Champions League on Wednesday night, is said to be set for a £32m move to Stamford Bridge over the summer, as Chelsea look to bolster their attacking options.

But Mourinho refused to be drawn on the speculation over his summer dealings.

‘The market is closed. It opens in the summer,’ he said.

‘Chelsea will be calm and quiet during that period, we are not going to be the noisy team buying and selling and selling and buying.

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Diego Costa scored against Chelsea (Picture: AP)

‘We are going to do a couple of critical signings.

‘Is he [Costa] a striker a target for us? Yes, we never denied that. Is Diego a good player? He is but he is an Atletico Madrid player, so we cannot say much.’

The Chelsea boss also remained coy on the future of on-loan goalkeeper Thibaut Courtois, currently in his third season with the Champions League finalists.

‘I prefer to say that he is Atletico Madrid’s goalkeeper,’ Mourinho said.

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