Pegula eliminates American compatriot and defending Australian Open champion Keys

Pegula defeated her fellow American and podcast partner 6-3, 6-4 in a match that showcased her control from start to finish.

Keys entered the contest as the defending champion and had won two of their three previous meetings, but Pegula dominated this encounter, racing to 4-1 leads in both sets and rarely allowing Keys to settle.

The defeat brought an end to Keys' first Grand Slam title defence, having navigated what was widely regarded as a tough section of the draw.

The win sends Pegula into an all-American quarterfinal against Amanda Anisimova, who also advanced on Day 9. Anisimova overcame Wang Xinyu 7-6 (4), 6-4 as temperatures climbed at Melbourne Park, prompting tournament organisers to activate the heat stress policy, which allowed for additional cooling breaks.

Anisimova arrives in strong form after finishing runner-up at both Wimbledon and the US Open, the last two majors.

Pegula has now reached the Australian Open quarterfinals for the fourth time, though she has yet to progress beyond this stage.

Her victory, alongside Anisimova's, ensured that four American players reached the women's singles quarterfinals - the first time since 2001.

"At least one of us will get through, and I think that's great for American tennis," said Pegula.

"Yeah, it's been pretty crazy how well the women have been doing and how many top-ranked girls there are. I'm just happy to be a part of that conversation."

Pegula and Anisimova advanced one day after world No. 3 Coco Gauff and 18-year-old Iva Jovic, who qualified from the opposite side of the draw, underlining the depth of American talent in Melbourne.

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