Barcelona are reportedly concerned about a £54m release clause in Samuel Umtiti's contract, which Manchester United are tempted to buy out.
The 24-year-old, currently nursing a hamstring injury, has adapted well to life at Camp Nou since joining from Lyon in a £25m deal last year.
According to the Daily Mail, however, Barca chiefs are bracing themselves for an approach to be made by United, while Manchester City are also known to be in the market for a centre-back.
In response the Catalan giants are said to be weighing up the offer of a new contract, which would see the value of the France international's release clause climb considerably.
Umtiti has been used 12 times in La Liga this term and on a further five occasions in the Champions League.
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