The 21-year-old signed a lucrative long-term deal shortly after bursting onto the scene in 2016 but hes been disappointed with his progress under Jose Mourinho.
Rashford wants to play in a central forward position but has found himself behind Romelu Lukaku and an out-of-form Alexis Sanchez.
Despite his struggles, Rashford remains one of the brightest prospects in Europe and Real Madrid are keeping a close eye on the England international.
United, understandably, are keen to keep Rashford and believe losing one of their academy products would send a bad signal around the world.
Rashford earns around £75,000-a-week at Old Trafford and United are willing to double his wages to convince him to stay at the club.
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Talks over a new deal stalled at the end of last season according to the Daily Star and United are keen to accelerate negotiations.
United face Crystal Palace at the Theatre of Dreams on Saturday and Rashford could start given the injury doubts over Lukaku.