Naomi Osaka crashes out of US Open with second-round loss to Karolina Muchova

Naomi Osaka’s return to the U.S. Open didn’t last long.

After a stirring, straight-set upset over 10th-ranked Jelena Ostapenko , Osaka looked capable of hanging around awhile in Flushing.

Instead, two days later, she bowed out in disappointing fashion, and Osaka had only herself to blame.

This wasn’t a case of necessarily losing to a superior player; Osaka beat herself after playing mostly mistake-free tennis in the brilliant opening-round performance.

Osaka committed 21 unforced errors in a 6-3, 7-6 (5) loss to unseeded Czech Karolina Muchova under the lights at Arthur Ashe Stadium on Thursday night.

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“It’s a little rough because I do take these losses really personally,” said the two-time U.S. Open champion, who grew up in nearby Elmont, N.Y. “It’s like a dramatic word, but I feel like my heart dies every time I lose. It sucks a lot, but I’ve been trying to be more mature and learn and talk more about them.”

In her first U.S. Open since 2022 — Osaka took time off to give birth to a baby girl Shai 13 months ago — she was too mistake-prone.

Of her 21 errors, 17 came in the second set, and there were also four double faults.

The game that turned the match came right after her one and only break of Muchova, which gave Osaka a 5-4 lead in the second set.

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But a series of Osaka miscues enabled Muchova — a semifinalist at the U.S. Open last summer who has seen her ranking plummet to 52nd in the world amid injuries — to break back despite facing three set points.

In the tiebreak, it was again Osaka unable to complete points.

She had a key double fault when up 4-2 in the tiebreaker.

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Facing match point, Osaka was unable to convert a swinging forehand volley at the net.

“I think, during the pressure moments, I got nervous, and I don’t know if I just have to keep playing more matches and get used to that feeling, especially on a really big stage,” she said.

In Osaka’s first year back on the WTA Tour after a 15-month maternity leave, she failed to advance past the second round of a Grand Slam. She has posted an 18-16 record.

But Osaka felt this year has been productive, even if the results haven’t been there.

Her goal is to one day rediscover the form that helped her win four major titles and rise to No. 1 in the world.

“Honestly, I feel like I’m coming back from pregnancy, but also it wasn’t like in 2022 I was like the best version of myself,” Osaka said. “So in some way, I had to catch up to that and then also I’m trying to pass it at the same time.”

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