The teenager has played for United's first team regularly this term, while also getting an England cap.
Advertisement
Advertisement
On Mainoo, Antonio told the Footballer's Football Podcast: "He is frightening, he is actually frightening.
The craziest thing is that when they came to us at the beginning of the season, I didn't know much of these players like and this was United, but when he played against us I was like ''his kid is something special'.
Then I was like where did they sign him from? They had to have signed him, this guy was a joke, but he came through the academy, this kid is something else."