Day six at the 2025 Argentina Open brought plenty of action as the semis rolled on to determine who’ll feature in Sunday’s decider.

It was a fairly straightforward affair for Francisco Cerúndolo (28), who beat Spain’s Pedro Martínez (41) 6-2, 6-4. Cerúndolo, the top-ranked Argentine in the ATP singles ranking, was after his second final in the tournament, having previously lost the 2021 decider against Schwartzman.

It was a tense start to the game, with both players holding on to their serve turns and looking evenly matched. But slowly, Cerúndolo’s faster, more explosive play pushed Martínez deeper, until he broke the Spanish’s serve at 3-2. He went on to win four consecutive games to wrap up the first set.

In the second set, Martínez came out determined, fighting for every point. Cerúndolo got a break at 1-1 but had to defend the advantage with claws and teeth, coming back from 0-40 with his serve at 4-3. He was able to serve out the game to seal the win.

“I think I’ve had some very good moments across the last four years, but I can’t say I’m playing my best ever tennis just yet,” said Cerúndolo during the post-match press conference. “I’m feeling good, played some very good four matches, but I’ll have to show it again tomorrow, sustain it over the next couple of months. I need to keep going into the future like this.”

The Argentine player, who became the fifth in history to reach two or more finals at the event, said a lot has changed since he reached the 2021 decider.

“Reaching that final came out of nowhere. I arrived there after battling every game, I wasn’t as prepared, tennis-wise or mentally. Now, it’s been four years, and I think I’ve learned a lot, improved a lot, I’m more experienced with all the stuff I’ve gone through, so I think it’s going to be a different kind of final, a better match.”

Brazilian phenomenon João Fonseca (ATP singles ranked 99) had a lot more trouble booking his place in the final, beating Serbia’s Lazlo Djere (112) by 7-6 (3), 5-7, 6-1.

The first set was a hard-fought battle. Djere, applying the gameplan that nearly took Argentina’s Mariano Navone to a semis spot, defended with deep groundstrokes from the baseline, trying to make Fonseca fall into erratic shot selection. This time, however, the Brazilian kept his cool, taking the first set to a tie-break, where his superior firepower secured him the win.

The second set looked to be more of the same, but the match took a tumble at 4-3, as Fonseca broke Djere’s serve and looked to serve out the game. His form faltered, however, and Djere claimed the break back. When it looked like the set was headed to another tie-break, Fonseca got a matchpoint in Djere’s serving turn. The Serbian fought back and then broke a disgruntled Fonseca’s serve to win the set.

That was about as much fight as the world number 112 had in him, as the Brazilian looked miles ahead in the third set despite calling for medical time on two occasions. Breaking Djere’s serve at 2-1 and 4-1, he won five games in a row to wrap up the game.

At 18 years and five months old, he became the second youngest Argentina Open finalist, just one month older than Argentina’s José “Chucho” Acasuso, who did it in 2001. He also became the first man born in 2006 or later to reach an ATP Tour semi.