And it seems like the Red Devils will place their faith in Mason Greenwood and Edinson Cavani when it comes to playing in the No 9 role.
United legend Wayne Rooney played alongside Ronaldo at Old Trafford.
And the Derby boss said on Thursday that he didn’t think the veteran would join City because he wouldn’t want to tarnish his legacy.
“I think Cristiano has got a very good legacy at Manchester United and I know how proud he is as a player and a person,” Rooney told talkSPORT.
“I can’t see [him joining City], but it’s football so you never know. There have been a few that have done it but no one at Cristiano’s level. Obviously Peter Schmeichel and Andy Cole, but I just can’t see that as an option for him really.