NEW YORK -- Naomi Osaka smacked a forehand winner into the open court, bringing Colin Kaepernick and Kobe Bryant to their feet in applause.

Osaka has power in her strokes and star power in her corner.

The defending US Open champion moved into the third round Thursday with a 6-2, 6-4 victory over Magda Linette, setting up a possible third-round showdown with Coco Gauff.

With Kaepernick and Bryant sitting with her team just a few rows off the Louis Armstrong Stadium court, Osaka did her part and waited to see if the 15-year-old Gauff would win her match later that night.

Kaepernick, the former San Francisco 49ers quarterback who three years ago began kneeling during the national anthem before games, has been working out in the area in hopes of getting another shot in the NFL. Bryant, the retired NBA superstar, came to the US Open on Thursday to promote "Legacy and the Queen,'' a new book that he conceived and that Osaka has supported.

Osaka was grateful for their attendance, she said, and motivated to win quickly so she wouldn't keep them in the sun too long watching.

The No. 1 seed gave them plenty to cheer along the way, especially the forehand winner on break point that gave her a 4-3 lead in the second set after Linette had grabbed the first three games.

Gauff was scheduled to face qualifier Timea Babos in the leadoff night match on Armstrong, where she picked up her first US Open main-draw victory Tuesday against Anastasia Potapova, coming from behind just as she kept doing during her run to the fourth round of Wimbledon in July.

"It's amazing at that age," Bryant said. "Not just the skills she possesses, but the poise."

While Osaka moved on, another two-time Grand Slam champion was eliminated when No. 6 Petra Kvitova was upset by Andrea Petkovic 6-4, 6-4. Wimbledon champion Simona Halep tried to avoid falling when she played Thursday afternoon.

Other early winners included No. 16 Johanna Konta, who routed Margarita Gasparyan 6-1, 6-0; and No. 20 Sofia Kenin, who swept past Laura Siegemund 7-6 (4), 6-0.