Chelsea midfielder Juan Mata's apparent discontent at Stamford Bridge has reportedly alerted Manchester United.
Blues boss Jose Mourinho was coy over the future of Mata earlier this week, insisting that he didn't want to sell the Spaniard but his "door was open".
Manchester United manager David Moyes was first linked with a move for the 25-year-old in the summer, and according to Manchester Evening News, the Scot is keeping track of any forthcoming developments at the West London outfit.
Mata has featured on 17 occasions for Chelsea during the current campaign, but many of his appearances have come from the substitutes' bench.
The former Valencia man also displayed his displeasure at being replaced early in the second half of Chelsea's 3-0 win at Southampton on New Year's Day.
