Venus Williams has returned to the quarterfinals for the ninth time at the Australian Open, where she first made the last eight on debut in 1998.
The 36-year-old, seven-time major winner had a 6-3, 7-5 fourth-round win Sunday over No. 181-ranked Mona Barthel, who won three matches in qualifying and then beat two Australian wild cards and Olympic gold medalist Monica Puig in the first three rounds.
Williams will next play No. 24-seeded Anastasia Pavlyuchenkova, who beat No. 8 Svetlana Kuznetsova, 6-3, 6-3, in the opening match of Day 7 at Rod Laver Arena.
Pavlyuchenkova's win over fellow Russian Kuznetsova left Williams as the only Grand Slam winner left in that quarter of the draw.
"I was really challenged to play my best tennis," Williams said. "It's wonderful to get through to the quarterfinals against an opponent who's on fire."
Williams hasn't advanced beyond the quarterfinal round at Melbourne Park since her loss to younger sister, Serena, in the 2003 final. But she hasn't lost a set en route to the quarterfinals this year. Against Barthel, she won 90% of points when she got her first serve into play, hit 31 winners and four aces while not serving any double-faults.
"This is what you do all the hard work in the off-season for," she said. "It's wonderful to be able to advance even further."
Barthel was the lowest-ranked player to reach the fourth round of the women's draw here since 2010
Defending champion and No. 1-ranked Angelique Kerber was playing CoCo Vandeweghe in the last night match.
It's a lot more crowded on the top quarter of the men's draw, which features matches later Sunday involving top-ranked Andy Murray against Mischa Zverev and Roger Federer against Kei Nishikori.
In a late match Saturday in Melbourne, Rafael Nadal had a good, hard look at the future before pulling a few tricks from his past to hold it back — for now.
The 14-time Grand Slam winner, still recovering from a couple of months off with an injured left wrist, rallied for a 4-6, 6-3, 6-7 (5), 6-3, 6-2 win over German teenager Alexander Zverev to reach the fourth round of the Australian Open.
The 30-year-old Spaniard finished stronger in the 4-hour, 6-minute match on Rod Laver Arena as Zverev, widely touted as a Grand Slam champion of the future, tightened up with cramping and nerves.
"I enjoyed a lot this great battle. I was losing the last couple of times in the fifth set and I said to myself, 'Today's the day,'" said ninth-seeded Nadal, who had lost eight of the previous nine times he'd trailed, 2-1, in a best-of-five-sets match.
Grigor Dimitrov and Richard Gasquet didn't start their third-round match until 11:58 p.m. local time, most likely the latest start for a match at the Australian Open.
After grinding through four games in 24 minutes, No. 15 Dimitrov picked up pace and finished off, 6-3, 6-2, 6-4 at 2 a.m. — well short of the Grand Slam record 4:34 a.m. finish for the match between Lleyton Hewitt and Marcos Baghdatis in 2008.
Nadal next will face Gael Monfils, who beat Philipp Kohlschreiber, 6-3, 7-6 (1), 6-4.
In another gripping five-setter, wild-card entry Denis Istomin followed his upset win over defending champion Novak Djokovic with a 6-4, 4-6, 6-4, 4-6, 6-2 victory over Pablo Carreno Busta.