Earlier this week, in a boardroom at Miami Gardens’ Hard Rock Stadium, 19-year-old Brazilian tennis phenom Joao Fonseca is doing the media rounds before the Miami Open begins. He’s dressed casually in a blue On T-shirt, a Whoop fitness band, and a Rolex with a fluted bezel.
For one social media clip, he tries—and fails—to balance a banana on a room divider using an Inspector Gadget-like extending arm. Next, he’s asked to name the ten youngest ATP 1000 tournament winners in history—a tough question even for a die-hard fan. Then the topic turns to movies. Though Fonseca doesn’t have much time to watch films, he did see the Oscar-nominated The Secret Agent, directed by fellow Brazilian Kleber Mendonça Filho and starring Salvador-born Wagner Moura.
While this kind of content is a staple (and sometimes a chore) of the modern era, what really stands out as I follow Fonseca is his presence. As we walk through the room, reporters, creators, and staff all turn to watch. Fonseca and his team can’t stop for everyone, but everyone wants a moment with him. The athlete himself moves with a confident stride—still lanky and long-limbed like a teenager, but self-assured. After two years on tour, with his profile and ranking skyrocketing over the last 12 months, Fonseca seems to have both leveled up and settled in.
“I think I’m understanding a little more about how the top players play—not technically, but mentally,” he says as we walk. “How to handle important points, how to start a match. I’m starting to learn more of the tricks.”
That growing understanding—and improvement—was on full display during Fonseca’s round of 16 match at the BNP Paribas Open in Indian Wells a few weeks ago. There, for the first time in his career, he faced world No. 2 Jannik Sinner, pushing both sets to tiebreaks and earning three set points in the first. With the eye-catching camouflage of his On gear and his explosive forehand, Fonseca looked like a genuine threat to Sinner’s dominance—and by extension, to that of Carlos Alcaraz. Over the past three years, Sinner and Alcaraz have become tennis’s most formidable duo.
“I knew there wasn’t much of a weakness I could attack with my power,” Fonseca says of the match. “I knew if I hit hard, it was coming back just as hard. So one of the biggest things for me against Jannik is maintaining consistency at the highest level. He just doesn’t miss.”
While the tennis world endlessly speculates about his potential to challenge Sinner and Alcaraz, Fonseca simply believes in himself. After breaking through last year at the Australian and Miami Opens, he won two tour titles later in the season. Though a lower back injury a few months ago has him slightly below his career-high ranking, his performance at Indian Wells suggests he’s back in form and better than ever.
“I’m feeling 100% now and good on the court,” he says. “We’re trying to improve my game, but also my mentality and my physique, so I can compete at the level I want—top five in the world. It’s also important for me to focus on the little things.” He’s been deliberately learning how to handle the endless downtime on tour, especially how to avoid overthinking. For Fonseca, that often means playing Catan with his team.
As we walk into the stadium’s center court area, Casper Ruud is warming up to our right and Flavio Cobolli is chatting to our left. Out here, the air itself seems tinged with a cyan glow, which complements both Fonseca’s shirt (though he prefers plain colors when he plays—“I’m a simple guy,” he says) and his golden eyes.
South Florida has a large Brazilian population, and Fonseca is already so popular in Miami that the tournament’sDirector and former pro James Blake has said that Fonseca should play on the tournament’s main court for as long as he remains in the draw. That spotlight seems all but certain for his second-round match later today against Alcaraz—yesterday, Fonseca battled through his opening match against Hungary’s Fábián Marozsán in three sets, earning this early test.
Fonseca wouldn’t want it any other way. “When I was younger, I was a bit shy on court,” he told me as we kept walking. “I used to feel the crowd more as pressure. Here it’s packed, it’s loud, it has that Miami energy… and it’s just amazing.”
He pauses, looking down the hall. “I’m more used to it now,” he says. “I’m ready.”
Frequently Asked Questions
Of course Here is a list of FAQs about how tennis star Joo Fonseca took his game to the next level designed to cover a range of interests from casual fans to aspiring players
About Joo Fonsecas Rise
Who is Joo Fonseca
Joo Fonseca is a rising Brazilian tennis star born in 2006 who gained major attention by winning the 2023 US Open boys singles title and quickly making an impact on the professional ATP Tour
What does taking his game to the next level mean in his case
It refers to his rapid transition from a top junior champion to a player who can compete with and beat established professionals on the ATP Tour showing a complete and powerful game beyond his years
What was the biggest turning point in his development
Winning the 2023 US Open boys title was a massive confidence boost but the real turning point was his subsequent performance at the 2024 Rio Open where he beat top100 player Arthur Fils and pushed former champion Cameron Norrie proving he belonged at the pro level
Technical Tactical Development
What are the standout strengths of Fonsecas game
His biggest strengths are his explosive allcourt athleticism a powerful and accurate forehand a surprisingly solid onehanded backhand and exceptional net skills He plays with aggressive highrisk tennis
How has his mental game improved
Hes known for playing with joyful fearless energy Taking his game to the next level involved channeling that passion into resiliencestaying focused under pressure against seasoned pros and not getting discouraged by mistakes
Did he make any major changes to his technique or strategy
Rather than overhauling his game he refined his aggressive style for the pro level This includes better shot selectionknowing when to unleash his power versus when to construct a pointand improving his firstserve percentage and return positioning
Training Support
Where does Joo Fonseca train
He is part of the Brasil Tennis Team a highperformance program led by former top50 player Thiago Alves which provides a structured national training environment with top coaches and sparring partners
What role does his team play in his development
His team including coach Joo Zwetsch and fitness coach Rafael Rech focuses on holistic development tailoring his