Serena moves into last eight at US Open

NEW YORK — Five-time champion Serena Williams reached her first Grand Slam quarter-final of 2014 at the US Open Monday but Canadian poster girl Eugenie Bouchard, struggling in the heat and humidity, was knocked out.

World number one Williams, the twotime defending champion, eased past world number 50 Kaia Kanepi, 6-3, 6-3, for a fourth win over the Estonian and 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 -- at last I did it," said the 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. 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."

Seventh seeded Bouchard was at the center of a medical drama on Louis Armstrong court when she had to have her blood pressure and temperature taken in her 7-6 (7/2), 6-4 defeat to Russian 17th seed Ekaterina Makarova.

Wimbledon runner-up Bouchard called the medical timeout at 2-3 down in the sec- ond set when she was obviously struggling in the 31-degree heat (87F) and humidity running at 60 percent.

She slipped 4-2 down, broke back for 4- 3 but left- handed Makarova was too strong for the ailing Canadian as she booked a spot in the last-eight for the second successive year.

"I was feeling very light headed and dizzy on the court, just seeing things a little blurry. I just generally didn't feel good," said Bouchard whose defeat meant that for only the second time in the Open era there will be just one top-eight seed in the quarterfinals of a major.

"It developed as the match went on. I have had a few late, tough matches here, and I don't think I fully recovered from those."

Bouchard's defeat ended her run of having reached at least the semi-finals at all the majors this year and also means that for the first time since 1977, the four Grand Slam women's championship matches will have featured eight different players.

Makarova next faces former world number one Victoria Azarenka, the runner-up to Williams in 2012 and 2013, who came back from a set down to defeat 145th-ranked Serbian qualifier Aleksandra Krunic, 4-6, 6-4, 6-4.