Five-time champion Serena Williams reached her first Grand Slam quarter-final of the year at the US Open on Monday, setting up a clash with Flavia Pennetta in a duel between the two oldest women left in the draw.
World number one Williams, eased past world number 50 Kaia Kanepi, 6-3, 6-3, for a fourth win over the Estonian.
"It's my first quarter-final of the year at the majors -- at last I did it," said the 32-year-old American, who had fallen in the fourth round in Australia, the third round at Wimbledon and suffered a second round French Open exit.
"It was a tough match today. I wanted to stay relaxed and told myself that whatever happens, Serena, you're still in the doubles."
Italian 11th seed Pennetta, also 32, reached her fifth quarter-final in New York with a 7-5, 6-2 victory over Australian 29th seed Casey Dellacqua.
Meanwhile, Maria Sharapova crashed out of the US Open Sunday while 17-year-old Belinda Bencic became the youngest women's quarter-finalist since 1997 giving Switzerland a double boost after Roger Federer had moved into the last-16.
Sharapova, looking to add this year's US Open title to her French Open win in June, was undone by 43 unforced errors and eight double faults as 10th seed Caroline Wozniacki won 6-4, 2-6, 6-2.
She will next face 13th-seeded Italian Sara Errani who ended the magical run of 32-year-old Croatian qualifier Mirjana Lucic-Baroni 6-3, 2-6, 6-0.
"It means so much to me," said 2009 runner-up Wozniacki, who reached the semi-finals in 2010 and 2011 but hadn't been past the third round at Flushing Meadows the last two years.
"It's been a bit up and down for me this season. To win today against a champion like Maria is an unbelievable feeling."
Sharapova, the 2006 champion, admitted she had been outplayed.
"I thought she played really well. She made me hit a lot of balls. That's always been her strength," said the Russian.
Bencic, 17 and ranked 58th, dismissed former world number one Jelena Jankovic 7-6 (8/6), 6-3 to become the youngest US Open quarter-finalist since Martina Hingis won the title in 1997 at the age of 16.