The Daily Mail says United and Napoli have begin tentative negotiations over the transfer of a player who never settled to life under David Moyes at Old Trafford last season.
Fellaini's agent denied suggestions on Monday night there was a meeting between the player and Napoli's technical director Riccardo Bigon at the Sheraton Hotel at Brussels Airport over the weekend.
However Fellaini is aware of Napoli's interest and that the club's manager Rafael Benitez believes he can turn him back in to the buccaneering forward player he was when he was at Everton and wants to utilise his physical presence.
On Monday, Fellaini was back in Manchester after his efforts with Belgium in the World Cup.
Because his country reached the last eight of the tournament, he was not required to join United's tour of America and was back at Carrington with compatriot Adnan Januzaj for physical testing.
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