By Shrivathsa Sridhar MELBOURNE (Reuters) -Endless queues outside Melbourne Park's 1573 Arena on a sunny Thursday afternoon gave casual fans the impression that a Grand Slam champion was in action, but a quick peek inside revealed the carnival atmosphere and explained the interest.

Joao Fonseca definitively introduced himself to the world as the latest teen sensation in men’s tennis, upsetting No. 9 seed Andrey Rublev in the first round of the Australian Open.

Fonseca was part of the 2024 lineup alongside Fils and Luca Van Assche of France; Michelsen, eventual finalist Learner Tien and Nishesh Basavareddy of the U.S.; Jakub Mensik of the Czech Republic and Shang Juncheng of China, who also goes by his Americanized name, Jerry Shang.

Brazilian teen Joao Fonseca was one of the first surprises of the 2025 Australian Open, after he defeated ninth seed Andrey Rublev. Check out all you need to know about this young talent.

Brazil have known about Fonseca’s talent known for some time, making his ATP Tour debut at his home tournament in Rio as a 16-year-old wildcard. Fonseca also got the chance to be a hitting partner for Alcaraz and Sinner ahead of the ATP Finals in Turin after winning the US Open junior title in 2023.

Joao Fonseca's impressive Grand Slam debut at the Australian Open showcased the young Brazilian's potential despite his second-round defeat to Lorenzo Sonego. Praised by top players like Carlos Alcaraz,

Joao Fonseca is the talk of tennis after his incredible win against Andrey Rublev on his Grand Slam debut at the Australian Open – and it has edged him towards one of the first big rankings targets of his career.

Joao Fonseca definitively introduced himself to the world as the latest teen sensation in men’s tennis on Tuesday night, upsetting No. 9 seed Andrey Rublev 7-6 (1), 6-3, 7-6 (5) in the first round of the Australian Open.