Paulo Sergio looked back on his Sporting academy years with a then-15-year-old Cristiano Ronaldo—remembering the early signs of an extraordinary will to win, relentless training habits, and a personality that could rub teammates the wrong way.
Portugal’s World Cup clash against Uzbekistan is happening under the glare of modern football, but the story of one of its era’s defining figures began in a Lisbon academy, long before anyone called Cristiano Ronaldo a global benchmark.
Paulo Sergio played with him in Sporting’s academy between 1999 and 2003. When Sergio joined Sporting from Oriental at 13. Ronaldo had already been there “a couple of years” after moving over from Madeira. At the start, Sergio didn’t think Ronaldo stood out at the level people later expect. He remembers seeing “decent ability. ” but not the kind of instant impression reserved for the standout names in a crowded. talented group.
Sporting at that time had “a great generation” of boys competing for attention. The attacking group was especially strong. with Edgar Marcelino. Fabio Ferreira and Sergio himself all going on to play for Portugal at youth level. Ronaldo, Sergio says, only began to look different after he moved up to the under-15 team in 1998.
That’s when the improvements became undeniable. Sergio describes a season where Ronaldo was one of the younger players. yet “everyone could see that there was something there. ” and that his progress was “completely out of the ordinary.” The change wasn’t just about raw talent. Sergio points to how technically prepared Ronaldo was—using “decisive” as the word he keeps coming back to.
He was fast and lean. Sergio says. “not a gram of fat on him. ” but also strong enough to beat his marker with physicality. Their matches also reveal how unusual Ronaldo’s game-reading was even at that age. For most of the season. Sergio says they played with three forwards—Sergio. Ronaldo and Edgar Marcelino—without fixed positions. swapping whenever they wanted as they chased chance after chance.
The most vivid part of Sergio’s memory is what happened after training ended. Ronaldo stayed late. He would take shots, practise free-kicks, work through “his repertoire of tricks,” and develop new ones. And when the rest of the squad went home, he wasn’t done.
Sergio says Ronaldo would “sneak into the gym” at the training centre to do extra weightlifting in the evenings. He also tells a specific incident that still makes the story feel alive. It was Ronaldo and a teammate, Jose Semedo, whose extra work was discovered. The coach gave them a “dressing-down” in front of the whole squad, and the squad found it funny.
Ronaldo carried on anyway. Sergio believes it even extended to practical details—he “took some of the weights back to his dorm room.” For Sergio, it’s the clearest early sign that the mindset that later became Ronaldo’s trademark was already there, even as a kid. “He was different,” he says.
Popularity didn’t come automatically for him at that age, either. Sergio remembers that he wasn’t widely liked. “Not everyone liked him,” he said, and that his will to win could spark conflict with team-mates. Ronaldo wanted everyone to be “perfect like he was.” He demanded a lot. expected the same level from others. and could be a difficult character. That drove wedges inside the group. and Sergio says “a lot of people took against him. ” even if he personally stayed on his side.
Sergio’s relationship with Ronaldo was built on competition. He describes himself as a natural competitor too. the kind of player who loved to pit himself against Ronaldo in training. He also recalls a different side away from the pitch: Ronaldo as “a top guy. ” always keen to help and up for a laugh. with a taste for mischief.
He remembers pranks that were silly on the surface but reveal a boy who didn’t treat himself like a hero. He would hide people’s socks in the changing room. Sergio recalls an episode where Ronaldo put heat cream in someone’s underwear. and a few minutes later the person was “itching like crazy.” The memories. Sergio says. came with genuine laughter.
In matches. two things stood out early: the way he would run at his man and the way he struck the ball. For Sergio. those were “early indicators.” He thought he might be watching a future star—perhaps not at the level Ronaldo would later reach. but at least someone heading toward first-team football at Sporting. That was the goal the academy was all working toward.
Ronaldo’s evolution also mattered. Sergio says Cristiano changed as a player during their years together. He became more agile and “much more of a dribbler.” Sergio links that to the Ronaldo later seen at Manchester United. After Ronaldo moved to Real Madrid. Sergio says. he “moved away from that. ” taking on different characteristics that made him the best in the world.
Sergio says they have remained in touch over the years. He feels “an immense pride” in what Ronaldo achieved. not only as a Portuguese person. but as a former team-mate who “played a small part” in his development back in those academy days. His message to Ronaldo is simple: keep enjoying football as much as he can. because “a career goes quickly. ” and never change from the person he has always been.
That Sporting story sits oddly far from today’s World Cup spotlight—but Sergio’s memories of late-night training, relentless self-demand, and the friction that came with it offer a straight line to the player the world now watches in high stakes moments.
Cristiano Ronaldo Paulo Sergio Sporting academy Portugal vs Uzbekistan 2026 FIFA World Cup Jose Semedo Al Nassr CEO