Since returning to tennis, Naomi Osaka has often faced stacked Grand Slam draws as an unseeded player — a recurring challenge that’s left her frustrated.

But after reaching the final in Montreal in late July, Osaka arrived in New York seeded at a major for the first time since her comeback. 

Now, she’s back in a Grand Slam semifinal.

The two-time US Open champion defeated No. 11 seed Karolina Muchova 6-4, 7-6 (3), Wednesday night to advance to her third semifinal in New York and fifth overall at a major.

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This one, though, carries added significance: it’s her first Grand Slam semifinal since becoming a mother.

“I’m really inspired by all the moms on tour,” Osaka said after the match. “But I also have this feeling like I’m not doing good enough or that I’m being left behind. And I think when all the moms came back and they did well off the bat, I sort of felt like something was wrong with me. I know that Belinda [Bencic] made the semis of Wimbledon, so I just really felt like I was losing a race in some sort of weird way.

“So yeah, that was on my mind, but now I’m here and I feel like a weight has been lifted off my shoulders.”

Watching her fire winner after winner in front of a roaring Arthur Ashe Stadium crowd, it was clear that Osaka had something to prove — and she delivered.

The opening set was tightly contested; with both players holding serve through the first nine games. The only break point in that span came in the very first game, when Muchova threatened early. Osaka erased it with a forehand winner — one of many she unleashed throughout the night.

Then, almost out of nowhere, Osaka broke Muchova in the final game of the set, forcing the Czech — who had reached the US Open semifinals each of the past two years — into a trio of uncharacteristic errors.

After the match, Osaka likened the play as you get deeper into a Grand Slam to boxing — “but with a tennis ball, obviously.”

To understand what she meant, all you had to do was watch the second set.

Following an off-court visit with the physio between sets, Muchova returned with renewed energy and broke Osaka to begin the second set. It snapped a streak of 18 consecutive service holds for Osaka.

But Osaka, showing the grit of a four-time Grand Slam champion and the resilience of a mother, broke right back.

And when Muchova broke again at 4-all, setting herself up to serve for the second set, Osaka responded with a forehand smash winner to break at love.

Locked into the moment, Osaka said she couldn’t recall what was going through her mind at that stage of the match.

“I honestly don’t even remember it,” Osaka said. “But she’s one of the toughest players that I’m able to play and I’ve played her so many times. She’s beaten me a couple of times and she beat me here last year, so I knew it was going to be a really tough match.”

After saving two break points, Osaka and Muchova traded holds to send the second set to a tiebreak. Before you could blink, Osaka raced out to a 6-2 lead. Two match points later, she sealed her place in the semifinals.

Among players who began their careers in the Open era, Osaka is the third woman to win each of her first five Grand Slam quarterfinals, joining Chris Evert and Aryna Sabalenka.

Speaking of Sabalenka, she’ll face Jessica Pegula in the first semifinal Thursday night. Meanwhile, Osaka will meet Amanda Anisimova with a spot in the US Open final on the line.

Anisimova holds a 2-0 record against Osaka at the WTA level, having won both of their previous meetings at Grand Slams in 2022 — first at the Australian Open, then again at Roland Garros.

Osaka anticipates a challenge as she looks for her first win against the American.

“It’s definitely going to be really tough,” Osaka said. “I’ve played her twice and I’ve lost both times. She’s so talented and she’s able to hit a winner from anywhere. So, I know it’s going to be tough, and I really like her as a person too, so I’m cheering for her.”

She smiled and clarified: “I’m not cheering for her against me, but yeah, it’s going to be fun. Plus, she’s American, and you know, this tournament means a lot to her as well.”