Mourinho was asked the motivation behind a probable new bid, despite United insisting Rooney is not for sale, and the Portuguese said David Moyes could always reject any fresh approach, just as Chelsea had from Barcelona for David Luiz.
"You try, because nobody forbids you to try," said the self-proclaimed Special One, who was speaking ahead of the clash with Aston Villa.
"When you think that you'd like to have one player and the market is open and the official bids are not forbidden, official bids are always accepted in an ethical way.
"Of course, the player's owners they can do exactly what we did in relation to David Luiz and Barcelona."
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