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 has long looked like a star-in-waiting. Under pressure in his first Grand Slam set, he delivered beyond those lofty expectations

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.