The Aston Villa skipper wears the number 10 shirt at his boyhood club, but with increasing speculation he could move to Old Trafford in the near future, he has revealed his second choice if Marcus Rashford kept his current jersey.
Responding to a fan during an Instagram Q&A, he said: "I used to love 7 growing up 'cause of Cristiano."
The iconic number seven shirt has been worn by a whole host of Red Devils legends over the years, including the likes of George Best, David Beckham, Bryan Robson and Eric Cantona.
Grealish's Villa teammate Conor Hourihane certainly doesn't think living up to its legacy would be too much, and he even insisted his captain is "too good" to remain at the club.
He recently said: "In terms of pure ability and sheer skill and technique level he's easily the best player I've played with to date.
"He's just got that gift. He runs quicker with the ball, when he faces someone up you're in real trouble. He's skipping by the best players in this league so easily.
"He's developed over the three years I've been here - he's taken his game to a new level - especially this year in the Premier League.
"He's taken it by storm really. You know, England team and getting that big move is only a matter of time because, if I'm being brutally honest, he's too good for our team at Aston Villa."