Greenwood has won just one cap for his country, with his sole appearance coming in a Nations League victory in Iceland a year ago.
"There is a ready-made superstar in Mason Greenwood," O'Hara told talkSPORT. “Why is he not playing for England?
“You're playing against Andorra. You know these games are coming up – give that man the games that he needs so we can get him ready for when the World Cup comes around, because he's the ready-made superstar in the making.
“I look at Mason Greenwood and I just think, that boy is a superstar talent – ready to be made into one.
“I don't know why they haven't used him. He's played one game for England. How has he only played one game for England?
“The guy is unbelievable. Mason Greenwood should be there in my opinion.
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