U.S. tennis queen Serena Williams crashed to one of the worst defeats of her glittering Grand Slam career on Monday, as Novak Djokovic and Andy Murray moved safely into the Australian Open quarterfinals.

Serena, winner of 13 major titles including five in Melbourne, fell to the lowliest of opponents on the sun-baked centre court in Russia's Ekaterina Makarova, the world No. 56 coming off a five-month losing streak.

But 30-year-old Williams, who injured her right ankle this month, was far from her best in the error-strewn, 6-2, 6-3 defeat and she admitted afterwards that she wouldn't have played if the tournament was not a Grand Slam.

The 2003, 2005, 2007, 2009 and 2010 winner, who missed last year's event with injury, has not suffered a similar Grand Slam defeat since 2005, when she lost to 85th-ranked Jill Craybas at Wimbledon.

Makarova, 23, whose victory stripped the competition of its last American singles player, is now into her first Grand Slam quarterfinal — after failing to get beyond a tournament first round since last August.

“It's an amazing feeling, it's unbelievable,” Makarova said. “She's an unbelievable player and I'm just really happy.”

Williams's exit blows a giant hole in the women's competition with Makarova, her next opponent Maria Sharapova, and Wimbledon winner Petra Kvitova the potential beneficiaries on her side of the draw.

Sharapova beat Germany's Sabine Lisicki and Kvitova overpowered Ana Ivanovic to reach the quarterfinals, where she will meet Italy's Sara Errani.

In the men's draw, defending champion Djokovic dropped his first set of the tournament against tireless Australian veteran Lleyton Hewitt before passing the late-night test 6-1, 6-3, 4-6, 6-3.

“I have give credit to Lleyton, who never gives up,” said Djokovic. “He's a great competitor and he obviously made me play an extra shot and I made a couple of unforced errors.”

Easy route

But Murray, who remains on course to meet Djokovic in the semifinals, took the easy route to the last eight when Kazakhstan's Mikhail Kukushkin retired injured with the scores at 6-1, 6-1, 1-0.

“It's so hot on the court,” said Murray, who played in the lunchtime heat.

“It's obviously good for me that I got to conserve a bit of energy. It's tough for him — it's his first fourth round in a slam, and he's obviously struggling.”

Murray's next opponent is Kei Nishikori, who became the first Japanese man in 80 years to reach the Australia quarterfinals when he shocked 2008 finalist Jo-Wilfried Tsonga in five sets.

Djokovic now plays Spain's David Ferrer after the fifth seed beat Frenchman Richard Gasquet in straight sets.

Kvitova reached the quarterfinals with a 6-2, 7-6(2) win over Ivanovic — but not before a temporary meltdown in which she embarrassingly swung and missed a simple overhead.

The cringe-making mistake late in the second set precipitated a brief nosedive and a flurry of errors but tough Kvitova steadied herself to seize control of the tiebreak.

Elsewhere on day eight, China's Zheng Jie was beaten 6-2, 6-1 by Italy's Errani to end her country's singles interest on Chinese new year's day, and a day after Li Na's tearful defeat to Kim Clijsters.

QUOTE OF THE DAY

My lefty serve is actually better than that. Maybe I should have started serving lefty — Serena who dished up seven double-faults and 37 unforced errors.

Keywords: Australian Open

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