Chelsea defender Kurt Zouma in action for the club.
But should the deals not go through they could swoop to sign France defender from the west Londoners.
Man United would need to move quickly with Everton also keen on his services as they look to strengthen their backline as well.
Old Trafford boss Jose Mourinho could have the upper hand though having signed Zouma for the Blues in 2014.
Chelsea are unwilling to sell but a late bid of a sufficient figure could prise the player away from Stamford Bridge, where he was set to stay until June 2023.
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