Mata’s future has been the subject of much speculation over the summer and although Mourinho previously rubbished suggestion of his sale Willian’s arrival at Stamford Bridge has further clouded the Spaniard’s role with the Blues.

The former Valencia man was mooted as a surprise makeweight in Chelsea’s first bid for Rooney but the club insisted the offer was a straight cash deal.

When asked about what would happen if United wanted Mata in exchange for Rooney Mourinho responded: ‘That’s hypothetical because they didn’t ask.

‘The two answers we got from Man United is “we don’t accept the bid” “we’re not interested in selling the player”.

‘That’s the only official contact we had with Man United. Till Monday we have nothing more to add to it.

‘We make the bid and they say no again. What do we lose? One email.’

Mourinho also suggested United should not be worried about selling Rooney to their rivals.

‘To me it is not a difficult decision because you want very much to keep Rooney or you don’t want to keep him?’ added Mourinho.

‘But that old-fashioned mentality of ‘I don’t sell players to clubs in the same country’ – I think doesn’t help.