Joao Fonseca, 18, becomes youngest Brazilian man to reach an ATP semifinal in Open Era

Joao Fonseca has made history in Buenos Aires, becoming the youngest Brazilian man to reach an ATP semifinal in the Open Era.

The 18-year-old from Rio de Janeiro came back from double match point down in the third set to defeat Argentina’s Mariano Navone, 3-6, 6-4, 7-5, and reach the final four at the ATP 250 clay-court event.

"Those are the victories we work for," he said after the two-hour, 53-minute marathon. "I was not playing my best but I fought until the end."

His previous-best results at the ATP level were two quarterfinals, both last year and both on clay, first in Rio de Janeiro last February (falling to Navone) and then in Bucharest last April (falling to Alejandro Tabilo).

The previous record for youngest Brazilian man to reach an ATP semifinal belonged to Thiago Seyboth Wild, who was 19 when he reached the semifinals—and eventually captured the title—at Santiago in 2020.

Fonseca had lost his only previous tour-level meeting against Navone, in the quarterfinals of his home tournament in Rio last year, and he was in all kinds of trouble in this one, too, not only dropping the first set, but twice going down a break in the second set at 3-2 and 4-3.

He got both of those breaks back and eventually pushed the match to a third set, but there was plenty more adversity to come.

Navone broke in the very first game of the third set and hung tightly to that break, eventually holding leads of 2-0, 3-1, 4-2 and finally 5-3, where he actually brought up double match point with Fonseca serving at 3-5, 15-40—but the Brazilian teenager just wouldn't give up, not only fighting off those two match points but eventually winning the last four games in a row (and 18 of the last 23 points) to close out an absolute thriller.

"Since the beginning I was believing I could win, even if I wasn't playing my best," said Fonseca, who finished the match with 34 winners to 60 unforced errors. "It's not easy against Mariano but I'm just very, very happy the way I fought today, and to reach my first semifinal."

The final points total: Fonseca 105, Navone 107.

Though Fonseca is ranked No. 99 in the world at the moment, his victory over the No. 47-ranked Navone should come as no surprise, as he's now won five of his last six matches against Top 50 players.

FONSECA VS TOP 50 PLAYERS SINCE OCTOBER (5-1):

• d. No. 20 Fils in '24 Next Gen ATP Finals RR
• d. No. 48 Mensik in '24 Next Gen ATP Finals RR
• d. No. 9 Rublev in '25 Australian Open 1st Rd
• l. to No. 15 Humbert in '25 Davis Cup Qualifiers RR
• d. No. 44 Etcheverry in '25 Buenos Aires 1st Rd
• d. No. 47 Navone in '25 Buenos Aires QFs

Awaiting Fonseca in his first ATP semifinal will not be another Top 50 player, though—instead it'll be No. 112-ranked Serbian qualifier Laslo Djere, who defeated Seyboth Wild earlier in the day, 7-6 (3), 6-3.

Djere is a former Top 30 player, though, peaking at No. 27 in 2019.