The 18-year-old missed the opening months of the 2023-24 campaign due to an ankle injury which he suffered while representing Man United against Real Madrid last summer.
Mainoo has been a vital player for the Red Devils since the end of November, though, and he is arguably now the first name on Erik ten Hag's team sheet due to the level of his performances.
The midfielder has turned out on 23 occasions for Man United this season, scoring three times, including a stunner against Liverpool in the Premier League on Sunday afternoon.
Mainoo made his England debut during the March international break, meanwhile, and he is now in a strong position to be named in Gareth Southgate's Three Lions squad for Euro 2020.
Real Madrid keen to bring Mainoo to the Spanish capitalAccording to Fichajes, Real Madrid have 'set their sights' on signing the youngster, with the Spanish giants keeping a close eye on his performances this season.
The report claims that his form 'has not gone unnoticed', and the midfielder 'could be tempted' to make the move to Carlo Ancelotti's side.
Man United are in a strong position when it comes to Mainoo's future, though, with his contract running until June 2027, with the option of a further 12 months.
The Red Devils are unlikely to consider any offers for the Englishman, meanwhile, with the club believed to be determined to build a new-look side around him.
As a result, Real Madrid are likely to be frustrated in their attempts to bring him in at this stage, but the Spanish giants are likely to keep an interest with a view to a move in the future.
Will Mainoo sign another new deal at Man United?A lot
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