Brazil legend Ronaldo hailed Zlatan Ibrahimovic as a "super professional" as he opened up on the Swede's trip to visit him in Ibiza this summer.
Ibrahimovic will turn 40 next month but he signed a new contract with AC Milan earlier this year which will keep him at San Siro until the end of the current season.
The veteran forward continues to defy his age and scored a remarkable 15 goals in 19 Serie A appearances last campaign to earn a recall to the Swedish national team.
Ibrahimovic spent the summer recuperating from a knee injury and took time to pay homage to Ronaldo, who many consider to be the greatest No. 9 of all time.
Ronaldo hosted Ibrahimovic and his family at his Ibiza pad this summer ( Image:
Buda Mendes - FIFA)
The former Barcelona, Inter, Real Madrid and Milan striker opened up on Ibrahimovic's trip during an interview with La Gazzetta dello Sport.
Ronaldo said: "Ibra is very strong, the years don't count for him. He's a rock, he has a body of a 30-year-old, not 40. He will guarantee the usual results because he knows how to manage himself like a super professional.
"He came to visit me in my holiday home in Ibiza. A fantastic day, we had fun, we talked a lot, about football and more. He arrived with his family, with his very good children."
Ibrahimovic is expected back from his injury after the international break and could return to fitness in time to face Lazio on Sunday and Liverpool in the Champions League next week.
"He is better physically," said Milan boss Stefan Pioli of Ibrahimovic in late August. "He hasn't yet rejoined the squad yet but next week will be very important as there will be a lot of ball work.
"If everything goes as well as I hope he could return to training with us (the squad) during the international break."
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Ronaldo spent one-and-a-half seasons with Ibrahimovic's Milan between 2007 and 2008, but he insists he will be cheering for Inter this season.
The 44-year-old spent five seasons with the Nerazzurri, winning the Ballon d'Or midway through his first campaign at San Siro.
"I'm an Inter fan, I maintain a special relationship with Inter and I always want them to win," said Ronaldo of his relationship with the club.
"The last championship was wonderful, we interrupted Juventus ' winning streak. It will be remembered for a long time.
"It's too bad that [Romelu] Lukaku has returned to England, but it's hard to resist when the top clubs in the Premier League call.
" Chelsea have made use of all their financial power. For me, the big favourites are still Inter. Lukaku left, but the team remains strong and balanced.
"They have brought in [Edin] Dzeko and made other significant signings, there are many interesting young players in the group."