Manchester City manager Pep Guardiola believes Manchester United striker Cristiano Ronaldo has the potential to still be scoring goals at the age of 75 - albeit in a much less competitive nature.
The City chief has made the admission on the eve of his side making the trip to Old Trafford for the first Manchester derby of the season, with both sides going in search of the local bragging rights.
Saturday lunchtime's big clash will mark Ronaldo's first appearance in a United shirt against City since 2009, in which he scored in a 2-0 win for the Reds at Old Trafford.
Since then, both clubs and Ronaldo's career have headed in different directions, with the five-time Ballon d'Or winner having excelled in both Spain and Italy, before returning to England in August.
The former Real Madrid man, despite United's recent troubles, has enjoyed a strong start to life back in England, scoring nine goals in 11 appearances in all competitions.
With his killer touch in front of goal showing no sign of weakening just yet, Guardiola believes Ronaldo will still be scoring goals even past retirement age, but has conceded it will be in much calmer and less pressured circumstances.
Guardiola told Sky Sports : "I think he has scored goals all his life and by the time he is 75-years-old maybe he will have retired, but at a BBQ maybe he will play a game and score goals.
"These types of guys, like Messi and him... all that they have done in the last decade in the world of football, scoring goals, goals and more goals, and helping teams to win speaks for itself.
"It is good for the Premier League, him coming back.
"I think United belongs to Cristiano and Cristiano belongs to United. It is a good fitting. It was in the past and maybe it will be good in the future."
Ronaldo, of course, did come close to joining City in the summer transfer window, but moved in United's direction after the Reds grew restless about the fact of him possibly joining their cross-city rivals.
Talks with former United manager Sir Alex Ferguson proved enough to convince Ronaldo to return to his former stomping ground.
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