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.

João 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.