MELBOURNE — Amanda Anisimova swept past China's unseeded Wang Xinyu into the Australian Open quarterfinals on Monday and set up a showdown with fellow American Jessica Pegula.

The fourth seed, who contested two Grand Slam finals last year, kept her cool as temperatures soared, beating Wang 7-6 (4), 6-4 on John Cain Arena.

She will play Pegula for a place in her first Melbourne Park semifinal after the 31-year-old disposed of defending champion Madison Keys in straight sets.

Anisimova and Pegula have met three times before, with the sixth seed winning them all.

"I'm feeling great. I mean, what a battle out there today. Tough conditions again, against a really good opponent. I've never played her before, she's playing some great tennis," said Anisimova.

"There were a lot of fans from China today, but honestly, it made the atmosphere so great. I don't find it disrespectful at all.

"They're just very loud, so they make the energy really fun."

Anisimova enjoyed a breakout year in 2025, reaching the finals of Wimbledon and the US Open, losing to Iga Swiatek and Aryna Sabalenka, respectively.

There was little to split her and Wang in the early stages, staying on serve until the 24-year-old American finally worked the first break point at 3-2.

But Wang saved and served out to keep the scores level.

Anisimova, though, slowly gained the ascendancy, and, after a hold to love, she made her move as Wang was serving to stay alive, earning a set point.

But, again, Wang snuffed out the threat to take it to a tight tiebreak, where Anisimova muscled her way through with some searing groundstrokes.

Neither player dropped serve in set one, but there were three breaks to start the next set, with Anisimova snaring two of them, before Wang took a medical timeout.

Wang seemingly gestured toward her groin when she called the physio and returned with heavy strapping on her upper right leg.

Pegula sent reigning champion Keys spinning out on Monday.

Keys and Pegula launched Day 9 in a clash at Rod Laver Arena between two Americans who know each other well.

They are good friends and also host the tennis podcast The Player's Box together, and had even been planning to record an episode on the eve of their match.

All that was put aside as a clinical Pegula dominated 6-3, 6-4 to set up a last-eight encounter with Anisimova.

Pegula, the 31-year-old sixth seed, is chasing an elusive Grand Slam title, with her best performance to date reaching the US Open final in 2024.

An erratic Keys made 27 unforced errors to Pegula's 17 and fired down six double faults as her title defense ended in the last 16.

The forfeit, as a part of a jokey bet with Pegula, will be a slice of apple pie with melted cheddar cheese on top.

"A bet is a bet, so I'll do it. I hope it's less gross than I think it's going to be, but we will find out," said Keys, who described herself as proud, despite the defeat.

Musetti blitzes Fritz

Fifth seed Lorenzo Musetti produced an inspired display to ease past Taylor Fritz 6-2, 7-5, 6-4 at Rod Laver Arena and reach the quarterfinals for the first time, setting up a meeting with 10-time champion Novak Djokovic.

"Honestly, I feel very proud. I know Taylor very well, we've played many matches, had many battles. And last time, in Turin, he was the winner,"Musetti said, referring to the pair's meeting at last year's ATP Finals.

Ninth seed Fritz, dug deep to stay in touch, but Musetti served out the victory in style for a tantalizing meeting with 24-time major champion Djokovic.

The Serb had advanced to the last eight after his fourth-round opponent Jakub Mensik withdrew due to an abdominal injury on Sunday.

"Novak, we've played many, many times and every time it's a lesson, first of all," said Musetti, who has won only one of their 10 meetings.

"It's such an honor to share the court with him, and every time I leave the court with something I really think is helping me to try to win against him."