The 19-year-old forward established himself as a key member of Ole Gunnar Solskjaer’s first team squad last season and has made 82 senior appearances in total, scoring 21 goals.
Greenwood had two years remaining on his previous Old Trafford deal, signed during the autumn of 2019, but the academy product been rewarded once again for becoming a regular under Solskjaer despite his young age.
“When you join the club at seven years old, you just dream of playing for the first-team one day,” Greenwood said.
“I’ve worked so hard to reach this level and the last two years have been amazing. There is so much that I want to achieve in the game and I know that this is the perfect environment to play my football.
“With the support from the manager, his coaching staff and so many great players to learn from; I know that I am developing every single day.
“There is a lot more to come from myself and this team and I am so committed to working hard week in, week out to help the group achieve success.
“I want to repay the club for the support that everyone has given me over the years and show everyone just what I am capable of.”
Solskjaer said that Greenwood had developed into one of the best young players in the country but added that it is United’s responsibility to ensure he keeps making progress.
“Whilst it is easy for people outside of the club to forget that Mason is just 19, it is our job as coaches to ensure he reaches his phenomenal potential and every step we take is to help him along that path,” the United manager said.
“Mason is naturally gifted and has a brilliant attitude; we know how important he is going to be for Manchester United over the coming seasons.”
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