The Chilean is expected to complete his move to Old Trafford after boarding a private jet to Manchester earlier today.
Mata, 29, is out of contract at the end of the season. United have the option to extend his stay by another 12 months, it’s understood they are yet to do so.
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The Spanaird’s contract situation has alerted former club Valencia, who are keen on signing him again.
Mata is believed to be happy at Old Trafford but the former Chelsea man is concerned that United are yet to trigger an extension clause and fears he could be on his way out.
The Spaniard joined United four years ago in a £37.1m deal from rivals Chelsea.
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