Naomi Osaka's forehand goes awry and she loses in the US Open's second round to Karolina Muchova

Seemingly back in her U.S. Open match, suddenly a point from getting to a third set, Naomi Osaka lost her way Thursday night, missing forehand after forehand until she ceded that game and chucked her racket, sending it clattering on the Arthur Ashe Stadium court.

Not much later, she was out of the tournament, eliminated 6-3, 7-6 (5) by Karolina Muchova in the second round of an event where Osaka won two of her four Grand Slam titles.

Osaka — once ranked No. 1 but now No. 88 after missing nearly 1 1/2 years because of mental health breaks and time off to have a baby — struggled for much of the early going, dropping five consecutive games and 22 of 26 points in one stretch.

But she played much better in the second set, getting her only break of the evening to lead 5-4 and yelling “Come on!” when 2023 French Open runner-up Muchova netted a forehand. The crowd roared for Osaka.

Serving for that set, Osaka hit a 119 mph ace, her fastest of the match, to lead 40-love. That gave her three chances to extend the match to a third set. That's when Osaka really faltered, making five forehand errors, with a double-fault mixed in, to get broken.

When they got to the tiebreaker, it was Muchova who asserted herself, then used some scrambling defense on the last point, flinging the ball back over the net and seeing Osaka send a swinging volley out.