NEW YORK - Five-time champion Serena Williams has reached her first Grand Slam quarter-final of 2014 at the US Open, while Canadian poster girl Eugenie Bouchard, struggling in the heat and humidity, was knocked out.
World number one Williams, the two-time defending champion, eased past world No.50 Kaia Kanepi 6-3 6-3 on Tuesday for a fourth win over the Estonian.
She goes on to face fellow 32-year-old Flavia Pennetta of Italy in a clash of the two oldest remaining players in the draw.
"It's my first quarter-final of the year at the majors and at last I did it," said the American.
"It was a tough match today. Kaia hits the ball very hard and moves the ball around really well. I wanted to stay relaxed and told myself that whatever happens, Serena, you're still in the doubles."
Italian 11th seed Pennetta reached her fifth quarter-final in New York with a 7-5, 6-2 victory over Australian 29th seed Casey Dellacqua.
Pennetta made the semi-finals in 2013, where she was defeated by Azarenka, and despite having a 5-0 losing record against Williams, she refuses to believe that the outcome of the quarter-final is a foregone conclusion.
"Of course she's better than me, but I still believe I can beat her. If she doesn't have a good day I can do that," said Pennetta of an opponent who has dropped just 17 games in four rounds so far.