Kerber sent packing in crazy day of upsets

World No.1 and defending champion Angelique Kerber has crashed out of the Australian Open at the hands of Coco Vandeweghe, joining Andy Murray as high-profile Day 7 casualties.

American World No.35 Vandweghe completely blew her German counterpart off the court, storming into the quarter finals 6-2, 6-3.

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Kerber's shock loss comes on the same day men's top seed Murray was also sent packing, beaten by unheralded German Mischa Zverev.

It's the first time in Australian Open history that both No.1s failed to make the quarter finals.

Kerber was no match for Coco. Image: Getty

Vandeweghe's victory sets up a quarter final clash with Spanish seventh seed Garbine Muguruza, who cruised to a straight-sets win over Romanian Sorana Cirstea.

It's just the second time 25-year-old Vandeweghe has made the quarter finals of a grand slam.

"Last year I came here and didn't win a match...and here I am now," she said after the match.

"My goal for this tournament was quarter finals and my year goal was semi final of a grand slam.

"Tonight was just another opponent in the way of my goals."

Serena Williams will now be a prohibitive favourite to claim a seventh crown at Melbourne Park, but on the basis of Vandeweghe's showing, she could also go all the way.

Kerber's loss continues a poor run for newly-installed female number ones.

Five of the last seven have been dumped from their first major as top seed earlier than the quarter-finals.

And should Williams take the crown, she will regain the world No.1 ranking from Kerber after spending 19 weeks as second banana to the German.

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