The Daily Mail claims the incident occurred when Greenwood, 21, was a “young player” at United.
The Red Devils cut ties with the striker this week following a club investigation into his behaviour following his January 2022 arrest.
Greenwood was suspended by United after being charged for attempted rape, assault and coercive control.
United then conducted their own investigation after the case was dropped.
And it remains to be seen whether Greenwood is now sold or loaned, or has his £75,000-a-week contract completely terminated.
The striker was once billed as the top young attacking prospect in England.
Greenwood netted 35 goals in 129 games for the Red Devils before his suspension.
And as a youth player in United’s academy, he caught the eye of huge names including Sir Alex Ferguson, Jose Mourinho, Ole Gunnar Solskjaer and Nicky Butt.
However, the Mail claims Greenwood once had a furious row during a training game.
It’s said he made a threat to quit Man United for cross-town rivals Man City.
On another occasion, Greenwood is said to have not turned up to training for an entire week.
In a statement after United’s conclusion of their investigation and decision not to reintegrate Greenwood into their squad, he said he “fully accepts” his mistakes while promising to continue playing elsewhere.
Greenwood added: “The best decision for us all, is for me to continue my football career away from Old Trafford, where my presence will not be a distraction for the club.
“I intend to be a better footballer, but most importantly a good father, a better person, and to use my talents in a positive way on and off the pitch.”
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