Manchester United are willing to pay up to £80m for Leicester centre-back Harry Maguire, Sky Sports News understands.
That figure would eclipse the current world record for a defender, which was set when Liverpool paid Southampton £75m for Virgil van Dijk in January 2018.
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Maguire, who phoned in sick for training on Monday, has four years left on his contract and Leicester's position all summer has been that he is not for sale.
The 26-year-old remains Ole Gunnar Solskjaer's No 1 target at Old Trafford and has told Leicester he wants to leave before the transfer window shuts on August 8.
Maguire is also said to be very keen on a move to Old Trafford so he can follow in the footsteps of his heroes Nemanja Vidic and Rio Ferdinand.
It is understood United would have to pay Leicester £90m for Maguire, further underlining the Foxes stance that they feel under no pressure to sell the player.
Sky Sports News understands Maguire is becoming increasingly frustrated with Leicester's stance towards selling him this summer.
United's executive vice-chairman Ed Woodward decided not to travel out to the club's pre-season tour of Australia, Singapore and China earlier this month to work on negotiations for incoming transfers.
The Red Devils are also trying to sign forward Paulo Dybala, 25, from Juventus in a swap move with striker Romelu Lukaku going the other way.
The deal between the two clubs "is as good as done", once source has told Sky Sports News, and the transfer now hinges on whether Dybala is convinced on a move to Old Trafford.
Juventus' sporting director Fabio Paratici flew into London this week to hold talks with United and the two players' agents "in order to reach an agreement and complete the exchange".
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