Wayne Rooney has claimed that his former teammate Cristiano Ronaldo can continue playing football until he is at least 40 years old.
The Portuguese international returned to England this summer when he re-joined Manchester United from Juventus for £12.86m, and he was brought straight into the starting lineup against Newcastle United on Saturday.
The five-time Ballon d'Or winner signed a two-year contract with the club, which would take him to the age of 38, but Rooney believes that he can continue past that.
The Derby County manager told Sky Sports News: "His ability is obviously one thing, but then he's also looked after himself massively... he's still in great condition. It wouldn't surprise me if he's playing until he's 40, like Ryan Giggs did, and still scoring goals.
"His teammates will have to work a little harder. But if it's anything like last time - towards the last two years of playing with him - the team allowed him to do that because he scores you goals, and goals win you games."
Ronaldo scored a brace on his return to Old Trafford at the weekend as the Red Devils defeated Newcastle United 4-1, taking his personal goal tally for the club to 120.