At just 18, João Fonseca is putting the tennis world on notice, as illustrated by his clinical straight-sets victory over ninth seed Andrey Rublev at the Australian Open.

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

Joao Fonseca has long been admired for his aggressive and mentally strong display on the court since turning pro last year. But on Tuesday (January 15), the Brazilian teenager stunned the tennis world by knocking out No.