Naomi Osaka looks all the way back as she surges into US Open semis

If anyone still did not believe Naomi Osaka’s game was all the way back, her gritty performance under the U.S. Open spotlight Wednesday night emphatically had to quiet the remaining doubters of the former No.1 player in the world.

Even herself, perhaps.

After crushing 2023 Open champion and American fan favorite Coco Gauff in straight sets in the Round of 16, Osaka moved into the semifinals of a Grand Slam tournament for the first time since returning last year from maternity leave and a mental break with a 6-4, 7-6 (3) victory over No.11 seed Karolina Muchova to kick off the night session at Arthur Ashe Stadium.

The victory sets up a clash in the semis with eighth-seeded American Amanda Anisimova, who dispatched No.2 Iga Swiatek on Ashe to conclude the day session.

The 27-year-old Osaka only has dropped only one set — to Daria Kasatkina in the third round — among her first five matches during this fortnight in Flushing Meadows.

Playing in her first Grand Slam quarterfinal since winning the Australian Open in 2021, the resurgent Osaka won 65 percent of her first serves, including five aces.

“That was a very difficult match…I’m just really grateful to be here,” Osaka said in her on-court interview. “It’s my first time [back] in a semifinal. I was up there watching and hoping for the opportunity to play on this court again.

The 2018 and 2020 U.S. Open champion was the top-ranked player in the world after capturing four major titles — also including the Aussie twice — through 2021 before missing the entire 2023 season to take care of mental issues and to give her birth to her daughter, Shai.

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Osaka has admitted uncertainty about getting back to this level of play, with two first-round ousters three second-round departures and two third-round advancements — including at Wimbledon earlier this summer — in her previous seven appearances at the majors since returning to the tour.

But Osaka’s confidence rose — as did her WTA ranking to No. 23 — with a run to the championship round of the Canadian Open in Montreal last month, and she has carried that over to New York under new coach Tomasz Wiktorowski.

Muchova had bounced Osaka, who was playing as a wild-card entry, in straight sets in the second round here one year ago.

Muchova dominated her first four service games, losing only two points, but Osaka also held serve throughout the first nine games of the match. After grabbing a 5-4 lead, Osaka capitalized on three unforced errors by her Czech opponent for her first break points of the night and seized the opening set at 15-40.

After Muchova took a brief medical timeout between sets, Osaka immediately dropped her first service game, But she evened matters with her second straight break before grabbing a 2-1 lead with a crisp backhand winner.

Osaka had the throngs roaring with a rush to the net for a forehand passing shot to go up 3-2, but she couldn’t hold that momentum as Muchova closed out for her next two service games to get to 4-4.

Osaka overcame one break point with a cross-court forehand but then sent a backhand barely wide to open the door for Muchova to try to serve for the second set.

The two-time Open semifinalist squandered that advantage, however, as Osaka got back on track with another Muchova unforced error on triple-break point for a 5-5 knot.

Osaka erased break point three times in the following game, and the New York crowd clearly appreciated her perseverance in as she yelled “come on” after grabbing a 6-5 lead.

Muchova made it to the tiebreaker, but Osaka’s baseline game was too strong as the crowd erupted once more as Muchova’s return sailed long on match point.