The six-time champion rallied from a set down against Tsvetana Pironkova, ending the unseeded Bulgarian's dream run in the quarterfinals.

"A match like today, I just feel like Pironkova was serving well, she was hitting winners everywhere," Williams said in her post-match press conference. "Maybe I wasn't being aggressive enough. So I think it's more or less me adjusting my game in the second set and coming back and just trying to do better."

The third seed has competed in three consecutive three-setters, prompting the question of whether she'll recover in time for her next match. She faces Victoria Azarenka, who soundly defeated 16th seed Elise Mertens in their quarterfinal encounter.

"It's not how you start; it's how you finish, right?" said Williams. "I just feel like, I'm okay. I'm ready to play three sets every match if I have to. It doesn't matter. A win is a win."

"I just gotta be a little bit better, really, and just expect people to go lights out and just be ready for lights out," said Williams, looking forward to the semifinal showdown.

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