Brazilian teenager Joao Fonseca saved two match points in defeating Mariano Navone at the Argentina Open on Friday to become the youngest ATP clay-court semifinalist since Carlos Alcaraz four years ago.
The 18-year-old came through 3-6, 6-4, 7-5 over home favourite Navone to reach his first tour-level semifinal.
Fonseca twice rallied from a break down in the second set and saved two match points late in the third, before sealing a two-hour, 53-minute victory.
"Those are the victories that we work for," said Fonseca, who is the youngest semifinalist on clay since Alcaraz at Umag in 2021.
"I was not playing my best and I fought until the end. Since the beginning I was believing I could win, even if I wasn't playing my best, but I fought and now I'm in the semifinals."
The 99th-ranked Fonseca, who was crowned the ATP's NextGen champion last season and started 2025 by stunning top-10 player Andrey Rublev at the Australian Open, will face Serb qualifier Laslo Djere for a place in the final.
Djere defeated Brazil's Thiago Seyboth Wild 7-6 (7/3), 6-3 to reach his 20th tour semifinal.