Top seeds bite the dust

Zverev stuns Murray; Vandeweghe packs off champion Kerber

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 quarterfinal with Zverev. 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.

It isn’t since the 2004 French Open that the top two men’s seeds have gone out before the quarterfinals, and for Murray, a five-time losing finalist, it meant yet more Melbourne misery. Zverev, a former junior rival of Murray’s, stretched to a series of elastic volleys to frustrate the Scot, coming to the net 118 times as he reached his first major quarterfinal.

Meanwhile Stan Wawrinka, who won the first of his three Grand Slam titles in Melbourne in 2014, came through 7-6 (2), 7-6 (4), 7-6 (4) against Italy’s Andreas Seppi. The formidable Swiss, now into his fourth Australian Open quarterfinal, will play France’s Jo-Wilfried Tsonga, who came from a set down to beat British surprise package Dan Evans.

Kerber’s maiden Grand Slam title defence, and first major tournament as world number one, ended poorly as she came off distinctly second-best to the aggressive Vandeweghe. The unseeded American broke Kerber’s serve four times and was on top at the net and from the baseline as she grabbed her first win over a world number one.

In the quarterfinals, Vandeweghe, who halted Eugenie Bouchard in the previous round, faces French Open champion Garbine Muguruza, who swamped Romania’s Sorana Cirstea 6-2, 6-3. Earlier Venus Williams, the oldest player in the women’s draw at 36, also became one of the first into the last eight when she beat German qualifier Mona Barthel 6-3, 7-5.

Her quarterfinal opponent is Anastasia Pavlyuchenkova, who beat fellow Russian Svetlana Kuznetsova 6-3, 6-3 to reach her first Australian Open quarterfinal in nine attempts.

Paes wins, Sania ousted
Meanwhile, India had a mixed outing as Leander Paes got off to a winning start in mixed doubles but fourth seeds Sania Mirza and her partner’s campaign in women’s doubles ended with a loss to an unseeded pair. Veteran Paes and Switzerland’s Martina Hingis won their first match against Australians Destanee Aiava and Marc Polmans 6-4, 6-3 to progress to the round of 16.

However, Sania was in for disappointment as she and Barbora Strýcová of Czech Republic lost to Japanese E Hozumi and M Kato 3-6, 6-2, 2-6 in a third round match that lasted one hour and 53 minutes. In mixed doubles though, Sania and Croatia's Ivan Dodig are in the second round, and so did Rohan Bopanna, winning their matches.

Results (prefix denotes seedings): Men: Singles: Round 4: 17-Roger Federer (Sui) bt 5-Kei Nishikori (Jap) 6-7 (4), 6-4, 6-1, 4-6, 6-3; 12-Jo-Wilfried Tsonga (Fra) bt Daniel Evans (Grb) 6-7 (4), 6-2, 6-4, 6-4; 4-Stanislas Wawrinka (Sui) bt Andreas Seppi (Ita) 7-6 (2), 7-6 (4), 7-6 (4); Mischa Zverev (Ger) bt 1-Andy Murray (Grb) 7-5, 5-7, 6-2, 6-4;

Women’s singles: Round 4: CoCo Vandeweghe (USA) bt 1-Angelique Kerber (Ger) 6-2, 6-3; 7-Garbine Muguruza Blanco (Esp) bt Sorana Cirstea (Rom) 6-2, 6-3; 13-Venus Williams (US) bt Mona Barthel (Ger) 6-3, 7-5; 24-Anastasia Pavlyuchenkova (Rus) bt 8-Svetlana Kuznetsova (Rus) 6-3, 6-3.