Matteo Berrettini won the seven games he played on Tuesday before Alex Molcan retired with a wrist injury in the second round of the Mexican Open.
The 26-year-old Italian, playing his first match since he lost to Andy Murray in the first round of the Australian Open on Jan. 17, won the first set 6-0 and was up 1-0 in the second when Molcan decided he could not continue.
Also Tuesday, top-seeded Carlos Alcaraz and fifth-seeded Cameron Norrie pulled out of the tournament.
“Unfortunately, I won’t be able to play in Acapulco. I have a grade 1 strain in my right hamstring that will keep me out for several days, according to the tests we did this morning,” Alcaraz said in a statement. “I’m really sad I can’t compete here, but now it’s time to think about recovering and being ready as soon as possible.”
Alcaraz, the US Open champion, captured his seventh career ATP title earlier this month at Buenos Aires, Argentina, and made it to the final last week in Rio De Janeiro, where he lost to Norrie.
Elias Ymer, who replaced Norrie in the main draw as a lucky loser, beat Adrian Mannarino 5-7, 6-3, 6-4 to earn a matchup with Berrettini in the next round.
Alcaraz's scheduled opponent, McKenzie McDonald, beat Luciano Darderi 6-4, 6-2.
In other results: Eighth-seeded Alex De Minaur beat Rodrigo Pacheco 6-1, 6-2; Nuno Borges defeated Nick Chapell 6-3, 7-6 (3); Brandon Nakashima outlasted Daniel Altmaier 6-3, 3-6, 6-1; and Jacopo Berrettini, Matteo’s brother, advanced in a walkover when Oscar Otte withdrew due to injury.