Joao Fonseca denied winning Rio Open homecoming by Alexandre Muller

A whirlwind week in Buenos Aires that culminated with a maiden ATP title caught up to Joao Fonseca on Tuesday evening.

Back at the Rio Open, the 18-year-old home favorite was halted by Alexandre Muller in the opening round inside Quadra Guga Kuerten. Muller moved forward, 6-1 7-6 (4), to set a second-round meeting with eighth-seeded Tomas Martin Etcheverry. The 25-year-old notably went down the week prior to Fonseca after being on the receiving end of 34 winners.

A year earlier, Fonseca produced his breakout moment at his home event when he blasted past Arthur Fils to become the first men's player born in 2006 to win an ATP match. He followed it up by ousting Cristian Garin, also in straight sets, to reach the quarterfinals. At the time, Fonseca was 17, ranked 655 in the world and had plans to attend the University of Virginia.

Flash forward 12 months and Fonseca has emerged as one of the ATP’s fastest rising stars. Having closed 2024 by lifting the Next Gen ATP Finals crown, Fonseca then claimed his Grand Slam main debut at the Australian Open with a Top 10 win over Andrey Rublev after beginning the new season with an ATP Challenger Tour title run in Canberra.

He came into South America’s lone ATP 500 on the back of triumphing over Francisco Cerundolo in Sunday’s Argentina Open final to crack the Top 70. A meeting with Brazilian superstar gymnast Rebeca Andrade was among the appearances that preceded Fonseca's match with Muller, but he was unable to carry his momentum further. For the Frenchman did not drop serve in the one-hour-and-34-minute victory to decisively advance.

Muller is also a first-time title holder in 2025, as he launched the new year by defeating Kei Nishikori in the Hong Kong Open final.