Jannik Sinner sidestepped the fate that befell his top rivals, advancing to the fourth round of the US Open, while fellow top seed Iga Swiatek gained momentum in her pursuit of a sixth Grand Slam title following a motivational chat with Serena Williams on Saturday. With defending champion Novak Djokovic ousted by a surprising defeat to Alexei Popyrin in the third round and title hopeful Carlos Alcaraz eliminated by Botic van de Zandschulp in the second round, all attention shifted to Sinner. The Italian, who has navigated the intense scrutiny sparked by a doping controversy before the tournament, dominated Christopher O'Connell 6-1, 6-4, 6-2, solidifying his status as the clear favorite in the year's final major.

"This sport is unpredictable, right? Whenever you dip in performance, whether it's mental, tennis-wise, or physically, it significantly impacts the outcome," Sinner commented on the departures of Djokovic and Alcaraz. "Both players who defeated them played exceptionally well. It happens." Sinner emphasized his focus on his own game, stating, "I just concentrate on what I need to do, which I believe I've accomplished, and then we'll see what I can achieve."

Next up for the Australian Open champion is Tommy Paul, who aims to end a 21-year drought for an American major winner since Andy Roddick's victory in New York. Paul, seeded 14th, rallied from a shaky start to defeat Canadian Gabriel Diallo 6-7(5), 6-3, 6-1, 7-6(3) and hopes to counter Sinner's aggressive style in their upcoming match. "He's undoubtedly the best ball striker on tour, and I'm not," Paul admitted. "I don't plan to engage in baseline slugfests with him. I intend to mix up my tactics."

In the women's draw, sixth seed Jessica Pegula moved forward with a 6-3, 6-3 victory over Jessica Bouzas Maneiro, but Ashlyn Krueger was defeated 6-1, 6-1 by Liudmila Samsonova. French Open champion Swiatek later showcased a near-perfect game in her 6-4, 6-2 win over Anastasia Pavlyuchenkova after a conversation with 23-time major winner Williams, who attended the US Open as a spectator after retiring in 2022.

"It was wonderful to see her. She exudes a lot of positive energy. It's great that she came to the venue and spoke with the players," Swiatek said, clearly impressed. "It was kind of her to approach me, as I certainly wouldn't have had the courage to do so if the roles were reversed. She's very nice and positive." Swiatek expressed her delight that Williams is following her career and cheering for her.

Roland Garros and Wimbledon runner-up Jasmine Paolini continued her stealthy progress by defeating Yulia Putintseva 6-3, 6-4, but she may face a significant challenge with Czech Karolina Muchova next. Muchova, regaining her top form after a 10-month hiatus due to a wrist injury, outperformed Anastasia Potapova 6-4, 6-2. Australian Alex de Minaur, despite recent injury woes, overcame a persistent hip issue to defeat Briton Dan Evans 6-3, 6-7(4-7), 6-0, 6-0. Evans, who had previously played the longest U.S. Open match in the professional era, finally exhausted his stamina.

Caroline Wozniacki demonstrated her continued prowess since her return in 2023 after a three-year hiatus following the births of her two children, easily dispatching Jessika Ponchet 6-3, 6-2. Briton Jack Draper, carrying the British hopes after Andy Murray's retirement, defeated Van de Zandschulp 6-3, 6-4, 6-2. Daniil Medvedev, the sole former champion in the men's draw, cruised past Flavio Cobolli 6-3, 6-4, 6-3 and aims to replicate his 2021 victory.

"It's the only Grand Slam where I have that opportunity," said fifth seed Medvedev. "I certainly didn't anticipate being in this position in the fourth round with Novak and Carlos still in the mix. It's a peculiar feeling—exciting yet daunting. I need to play at my best to try to win it again."