Nani is still to agree new terms at Manchester United.
The Manchester Evening News says Sir Alex Ferguson remains convinced Nani can fulfil his considerable potential and consistently produce the type of ability that he has so far only shown in flashes during his five years at the club.
But the longer his contract negotiations drag on, combined with the form of Valencia, could see Ferguson lose patience with the Portuguese and cash in.
And the potential arrival of Sao Paulo star Lucas Moura could force the issue before the market shuts next month.
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