Berbatov moved to Old Trafford from Tottenham in 2008/09, Ronaldo’s final season with the Red Devils before his then-world-record transfer to Real Madrid.
And Berbatov said the mentality that has led the Portugal captain to five Champions League trophies, five Ballon d’Ors and countless other honours throughout his career was constantly evident on the training pitch.
“Training sessions were like a war sometimes,” Berbatov told Betfair.
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“People in that [United] squad hated to lose, it was a great environment to feed determination and hunger to win.
“You could see how competitive [Ronaldo] was by just looking at his training schedule. He trained so hard, he was determined to be better than everyone else.
“You could also see it in the small training games we had or in matches; if he missed a chance or the side was losing, he was always determined to be a winner. We all had this side to us, that’s why we played for United.
“I was lucky to play alongside Ronaldo for a season. He was 100 percent professional, on the training pitch and off it. I don’t remember him ever being late for training. He was always preparing in the gym, after training he would stay and do extra work like working on his shooting, then he would go swimming and go to the gym again.
“Away from the pitch, Ronaldo would make jokes, he’d laugh at himself and he was friendly to everyone. I remember at the players’ Christmas party he was fun, one of the boys, but he didn’t drink and that was him all over – totally focused and professional.”
Ronaldo left Real Madrid for Juventus in 2018 and has won Serie A in each of his two seasons at the Italian club so far.
The forward also captained Portugal at Euro 2016 as they went all the way, defeating hosts France in the final.
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