Elena Rybakina defeated Polina Kudermetova via retirement in her Ningbo opener and followed it up with her first completed match win as World No. 1 on Friday night, overcoming a spirited challenge from Katarzyna Kawa for a 6-1, 3-6, 6-1 quarterfinal victory in 1 hour, 45 minutes.

The win sends Rybakina to her second straight Ningbo semifinal as she attempts to defend her title. To get there, she had to overcome a second-set dip that allowed Kawa to claw back after a dominant opening set.

"I actually started pretty well," Rybakina said in her on-court interview. "Everything was going in. The serve was working. Then in the second set I dropped a little bit. [There] was not enough energy on the serve, some mistakes here and there, and very cold games. Also, she played really well a few moments, so it changed in the second set pretty quickly.

"But I'm happy that in the third set I stayed aggressive and kept on playing my game."

After a season-long race, the world's top players converge in the California desert with the WTA's biggest title still to be won.

Rybakina finished the match much as she began it. After racing to a 3-0 lead in the opening set, the World No. 1 won the first three games of the decider before Kawa got on the board at 3-1. Rybakina then reeled off the final three games to secure her place in the semifinals.