Ronaldo's future at Old Trafford has been clouded by uncertainty following Man United's failure to qualify for the Champions League.
He could end up playing in the Europa Conference League next season, with his side languishing in sixth place in the Premier League table.
While Man United have endured a tough season, Ronaldo has enjoyed another prolific campaign having scored 24 goals in all competitions.
Despite his goals, Ronaldo has been the subject of intense speculation with his sister stoking the transfer flames on Instagram.
A Ronaldo fan account @cr7.o_lendario suggested the 37-year-old should leave Old Trafford in a bid to win trophies.
Ronaldo's sister, Katia Aveiro, appeared to back the idea of Ronaldo leaving Man United by liking the post, which has since been deleted.
The Instagram post reads: "It's very sad to see Cristiano Ronaldo in this situation with this Manchester United team. Now we are without a place in the Champions League.
"Cristiano does not have to stand [stay] as proof of love for the club, the greatest proof of that was he returned to Manchester United having also had a proposal from Manchester City with clearly a much superior squad, coach and by recent history.
"Cristiano has to think about Cristiano now. Manchester United will still last another thousand years. Cristiano, you have four more, five years of your career. Look for a better team now because you deserve it and because you still have a lot of football [trophies] to win."
Ronaldo still has another year to run on his current contract, with Man United having the option to extend it by a further year.
His place in the team is also unclear with Erik ten Hag set to replace Ralf Rangnick at the end of the season.
Asked about the five-time Ballon d'Or winner's Man United future, Rangnick replied: "This is a question you need to ask Erik ten Hag.
"He's showed that he can still be a vital part of this team, but it's obvious the team needs some more strikers."
Featured Image Credit: Instagram/PA
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