Dimitar Berbatov has lifted the lid on how Cristiano Ronaldo has become one of the greatest players of all time.
The two played together for just one season at Manchester United - the 2008-09 campaign - but they helped the Red Devils win the Premier League and the League Cup as well as reach a the Champions League final.
It is clear that Berbatov was impressed by what he saw from Ronaldo.
And speaking in an interview with Betfair he said he was most struck by the Portuguese superstar's constant professionalism and determination to become the best player of all time.
"I've been a lucky guy to share a season with him, every training session with him was like a war, but I didn't think anything was bad about wanting to win everything," Berbatov said.
"He was a good kid, he was fun and affectionate, but even at the Christmas parties he was very professional, I never saw him drink even at those events.
"He took extreme care of himself; he came to training early and was in the gym, and then he would stay late to practice his shooting on goal. Then he would finish by going swimming before being back at the gym. He was determined to be the best."
Ronaldo got the better of long-time rival Lionel Messi this week when he scored two penalties to help his Juventus side beat Barcelona 3-0 in the Champions League.
But Berbatov refused to get drawn into the debate of who will be remembered as the better of the two, adding: When Cristiano retires, of course, other stars will arrive.
"However, until he and Messi hang up their boots, we will not realise the size of these two athletes that we've gotten used to watching every day."
