Fourth seed Amanda Anisimova of the United States came from behind to beat second seed Iga Swiatek of Poland 6-7 (3), 6-4, 6-2 on Wednesday, advancing to the semifinals of the WTA Finals.

Amanda Anisimova of the United States returns a ball during the round robin match against Iga Swiatek of Poland at WTA Finals tennis tournament in Riyadh, Saudi Arabia, Nov. 5, 2025. (Xinhua/Luo Chen)

With Elena Rybakina of Kazakhstan having already secured a semifinal spot as winner of the Serena Williams group, Anisimova and Swiatek, both with one win and one loss before the match, faced off in a decisive showdown for the remaining semifinal berth.

The two had met twice earlier this year, as Swiatek swept 12 straight games to dominate the Wimbledon final, while Anisimova got her revenge in the U.S. Open quarterfinals.

In the opening set, both players held serve tightly. Although Anisimova earned four break points, Swiatek saved them all and prevailed 7-6 (3) in a tiebreak after the first 12 games went on serve.

The second set remained highly competitive. Anisimova saved three break points in the third game to hold serve, and the two traded holds until 5-4. In Swiatek's fifth service game, the American seized her chance for a crucial late break, winning the set 6-4 to level the match.

In the decider, Anisimova continued to apply pressure on Swiatek's serve.The Pole saved the first service game, but double-faulted on break point in her next game. Leading 5-2, Anisimova broke again to close out the match 6-2 and complete the comeback victory.

"The first set was super tough," Anisimova said afterwards. "I think I just made less errors in the second and third set, I was trying to play higher percentage tennis and just keep going for it. I think I was going for my serve a lot more. I just knew that I was going to have to step my level up a little bit if I wanted to win the match in the end."

In the group's other match on Wednesday, in-form Rybakina continued her impressive run, defeating Russia's Ekaterina Alexandrova, who entered as an alternate, 6-4, 6-4 to claim her third consecutive group-stage victory. Rybakina's original opponent, America's Madison Keys, had withdrawn before the match due to illness.