NEW YORK - Former world No. 1 Naomi Osaka lost to Amanda Anisimova of the United States 6-7(4), 7-6(3), 6-3 in the U.S. Open semifinals on Thursday, meaning the Japanese misses her chance to play for a fifth Grand Slam title and first as a mother.

The 2018 and 2020 winner of the tournament, Osaka remains winless against Anisimova, having lost both of their past meetings in 2022 at the Australian Open and French Open.

After giving birth to her daughter in July 2023, Osaka's semifinal run was her deepest at a Grand Slam since her 2021 triumph at the Australian Open, the tournament she also won in 2019.

Her straight-set wins over U.S. star Coco Gauff and Karolina Muchova of the Czech Republic in the previous two rounds, however, signal the 27-year-old has reclaimed her place among the world's best.

After both players secured double breaks in the first set, a double fault from Anisimova in the tiebreak put Osaka ahead 3-1, a lead she would not give up as she closed out the first frame.

Osaka gave up a break in the opening game of the second but broke back immediately as Anisimova began to utilize the drop shot to unsettle the rhythm of Osaka, who finished the match with 15 aces to the American's seven.

After trading breaks for 3-3 and again for 5-5, the latter via one of Anisimova's seven double faults of the encounter, Osaka survived two break points to hold serve in the following game but went 4-0 down in the tiebreak before dropping the set.

In the decider, Osaka gave up a break to go 3-1 down and then trailed 5-2 before nearly mustering a late comeback.

After holding serve, she saved two match points to force deuce in what turned out to be the deciding game, only to find herself unable to capitalize on two break points at the end of the near three-hour marathon.

Anisimova now faces last year's winner and current world No. 1 Aryna Sabalenka of Belarus in the final after she beat Jessica Pegula of the United States 4-6, 6-3, 6-4 in the other semifinal.