Ronaldo looks to be edging ever closer to an exit from Old Trafford as his relationship with Erik ten Hag reaches breaking point.
The Dutch boss confirmed Ronaldo refused to come on as a substitute in their midweek 2-0 win over Tottenham.
With United potentially looking to release Ronaldo in January, ahead of his contact expiring in June, ten Hag is on the hunt for a new target.
The former Benfica winger has struggled for consistency in the Spanish capital and he wants a fresh start with a starting role.
Mendes is also working on potential moves for Ronaldo, with a Champions League offer unlikely, he could join MLS side Inter Miami.