Former World No. 1 Carlos Alcaraz headlines the Stadium Court field on Day 4 of the Rolex Shanghai Masters Saturday.

The recently minted Tokyo champion plays Argentine Juan Manuel Cerundolo for the first time since they met at the Next Gen ATP Finals in 2021. They will begin the night session at 6 p.m. local time.

Their careers have taken different directions since Alcaraz won that contest in four sets. But World No. 55 Cerundolo has enjoyed his best season this year with 19 wins and a surprise victory over Jannik Sinner at Roland Garros when the Italian wilted in the heat after being on the cusp of victory.

Alcaraz is 32-4 on the year and returning to some of his best form after winning his third title of the year (and 27th overall) in Tokyo earlier this week.

“I'm feeling fresh mentally, which for me it's the most important thing,” Alcaraz said in his pre-tournament press conference. “I'm ready to take the challenge of this tournament. If we see a couple years back, probably this swing or this part of the season, it's never been my best one.

“Right now, I just want to be in a good state for this tournament, because I really want to win the tournaments, this one and the tournaments that I have in a couple months at least one day. So right now, I think it's an extra boost that I have for the rest of the season.”

Defending champion Valentin Vacherot opens his campaign against Argentine Sebastian Baez. Vacherot, 27, comes into the tournament at a career-high No. 14 in the PIF ATP Rankings but under enormous pressure to defend the 1,000 points he won here last year.

Vacherot, who last year had to come through qualifying, enjoyed tough wins in Beijing over Alexander Blockx, Stefanos Tsitsipas and Arthur Fils before falling to Jiri Lehecka.

Fourth seed Felix Auger-Aliassime, who is on track to qualify for the Nitto ATP Finals, opens the day session on Stadium Court against Camilo Ugo Carabelli.

China’s Buyunchaokete follows against former World No. 2 Casper Ruud.