Federer advanced to quarterfinals of Australian Open

World number ones Andy Murray and Angelique Kerber both crashed out of the Australian Open on a day of major upsets Sunday, as Roger Federer fought his way closer to an 18th Grand Slam title.

Murray was stunned by 50th-ranked serve-and-volley specialist Mischa Zverev in four sets before Kerber, the women's title-holder, tamely succumbed 6-2, 6-3 to Coco Vandeweghe.

The unpredictable results, following six-time champion Novak Djokovic's stunning loss in the second round, opened the door to a host of challengers -- with Federer leading the charge.

The 35-year-old Swiss won the last of his record 17 Slam titles in 2012, but he took full advantage of Murray's demise with a 6-7 (4/7), 6-4, 6-1, 4-6, 6-3 win over Kei Nishikori.

Federer, who looks back to full fitness after a six-month injury lay-off, said the hard-fought, fourth-round win could be significant as he now eyes a quarter-final with Zverev."This is a huge moment for me in my career," Federer



said."I was telling myself, 'Stay calm'. I feel fit, I've trained as hard as I possibly can in the off-season. That's what you tell yourself and you hope it pays off," he added.

Murray had been the hot favourite after Djokovic's shock exit, but the Briton lost 7-5, 5-7, 6-2, 6-4 to Germany's Zverev to extend his wait for a first Melbourne title.

The Briton was never expected to be troubled by the 29-year-old, who has never won an ATP title, but he suffered his earliest Melbourne departure in eight years.

It isn't since the 2004 French Open that the top two men's seeds have gone out before the quarter-finals, and for Murray, a five-time losing finalist, it meant yet more Melbourne misery."I've had tough losses in my career in the past. I've come back from them. This is a tough one," Murray said.

"I'm sure I'll come back okay from it. But right now I'm obviously very down because I wanted to go further in this event, and it wasn't to be."