The 20-year-old is an ideal long-term replacement for any one of those players, and his undisputed talent is attracting admiring glances from a host of top European clubs.
His versatility and two-footedness are two big sought-after assets, and Barca president Joan Laporta is said to be a big fan of the Bradford-born forward.
He has scored five goals and registered two assists across 17 appearances across all competitions this season, with his most recent goal coming in a 4-2 defeat to Leicester City in October.
Greenwood also found the net in the Red Devils' first three matches of the season, in 5-1 wins over Leeds United and Wolves, as well as in the 1-1 draw with Southampton that was sandwiched between those two fixtures.
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