While an ex-teammate of Cristiano Ronaldo witnessed everything the Portuguese star was capable of on the field, he revealed that the attacker is the only player whose private part he has not seen.
Rafael van der Vaart represented Real Madrid between 2008 and 2010, coinciding with the 39-year-old's time at the club, which allowed the former Tottenham Hotspur star to witness the five-time Ballon d'Or winner's work ethic first-hand.
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That mentality is evident even today, as Ronaldo is still going strong, contributing 15 goals and three assists in 18 games for Saudi Pro League outfit Al-Nassr so far this season.
Van der Vaart, while speaking on talkSPORT radio's TheLineUp podcast, described the Portugal international's elite mentality and admirable work ethic in a bizarre manner.
"He never left the house! I always tell this joke: Ronaldo is the only player whose penis I've never seen. He was always the first one to train and the last one to leave," he said, per the Daily Mail.
The 41-year-old continued: "First of all, his body, wow. He was a machine. He was a little ahead of his time; players today do the same. But his training in the gym, his diet, his sleep—all of that was more important to him than training extra hard [on the pitch]."
"He was incredibly selfish," the Dutchman added. "If we won 6-0 and he didn't score, he wasn't happy. But when we lost, he was happy if he scored two.
"Did he play just for himself? No, it was just his need to score. Ruud van Nistelrooy was the same.
"We had a lot of conversations with him, and it was very interesting because he kept saying: 'I need my goals'."
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The former Manchester United star brought his total career goals tally to 915 when he netted a double during Al-Nassr's Saudi Pro League encounter against Damac FC on Friday, leading his side to a 2-0 victory.