For the second straight round, No. 2-seeded Serena Williams drew a former top-10 player, onetime world No. 5 Lucie Safarova. And for the second time, Williams emerged unscathed.
Serena Williams will meet Caroline Wozniacki in the semifinals of the WTA Finals while Simona Halep will take on Agnieszka Radwanska.
Simona Halep beat two-time defending champion Serena Williams 6-0, 6-2 at the WTA Finals on Wednesday, with the American's two games won equaling her career worst.
Caroline Wozniacki credited her training for next month's New York Marathon as a key factor in her victory over Maria Sharapova in a grueling three-set match in the WTA Finals on Tuesday.
Serena Williams says comments by the head of the Russian Tennis Federation referring to her and older sister Venus as "brothers" were bullying, sexist and racist, and that she supported the one-year suspension imposed by the WTA against the official.
Serena Williams ended a difficult-for-her Grand Slam season in the best way possible, winning her third consecutive U.S. Open championship and 18th major title overall.
