Defending champion Angelique Kerber crashed out of the Australian Open in the fourth round with a straight-sets defeat to the magnificent Coco Vandeweghe.
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Kerber became the second world number one to bow out in Melbourne on Sunday, losing 6-2 6-3 under the lights at Rod Laver Arena after Andy Murray had been stunned by Mischa Zverev.
Top seed Kerber had no answer to an inspired Vandeweghe, who will face Garbine Muguruza in her first Australian Open quarter-final.
Unseeded American Vandeweghe started with a battling hold and set about putting Kerber under pressure with some heavy hitting, unleashing a barrage of thunderous forehands.
The Kerber serve was not in full swing, while her returns also lacked venom and Vandeweghe took advantage, breaking to take a deserved 4-2 lead.
Vandeweghe broke for a second time to go a set up, but Kerber hit back by winning the first two games of the second, only for the world number 35 to level at 3-3 after executing a sumptuous forehand winner with power and precision to earn three break points.
The force of Vandeweghe's hitting was too much for Kerber, who was broken again to trail 5-3 and the left-hander was shell-shocked as the California-based 25-year-old served out the match to break new ground in this tournament following what was surely the performance of her career.
STATISTICAL BREAKDOWN
Coco Vandeweghe bt Kerber [1] - 6-2 6-3
WINNERS/UNFORCED ERRORS
Vandeweghe – 30/20
Kerber– 7/15
ACES
Vandeweghe – 6
Kerber – 0
BREAK POINTS WON
Vandeweghe – 4/6
Kerber – 1/1
FIRST SERVE PERCENTAGE
Vandeweghe – 51
Kerber – 59
PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE
Vandeweghe – 78/54
Kerber – 58/39
TOTAL POINTS
Vandeweghe – 57
Kerber – 40