The world no.1 was dumped out of the Australian Open last night by the hard-hitting American in straight sets, losing 6-2 6-3 in just over an hour.
The result was an abberation for Kerber, who had previously won 17-straight matches at the hardcourt majors, claiming last year’s Australian and US Opens.
But her departure is very much in keeping with the tone of the tournament, which has seen top four seeds Andy Murray, Novak Djokovic, Aga Radwanska, Simona Halep and now Kerber leave in the opening week.
The 29-year-old was very matter-of-fact about the loss, downplaying the result and refusing to be downbeat about her 2017 prospects.
But she was at a loss to put her finger on the cause of her lacklustre showing.
That was not my game I play normally
“I was not feeling the ball at all tonight. I was not playing good from the first point,” she said.
“I make a lot of mistakes. I think that was not my game I play normally.
“My preparation was like I wanted and everything was fine. I came here to play good tennis, playing round by round, trying to continue my run from last year.
“But this is tennis, and you have good days and bad days. For sure today was not my best day.”
Kerber said she wasn’t sure if the collapse was due to the pressure of playing a first major as the world no.1.
“I have to a little bit of a think about everything what’s happened like the last few weeks, what I can take to the next tournaments,” she said.
“(Being no.1 and a favourite) are new experiences. They are new challenges. I can learn from all the other stuff which is new for me.
“It’s just the beginning of the year. I can still improve my tennis.”
Vandeweghe was irrepressible on Rod Laver Arena, winning in an hour and eight minutes.
Hitting 30 winners to seven, the 25-year-old completely exasperated Kerber, who was powerless and showed it.
“It’s really special to play a number one player in the world on any stage. I believe its my first number one win so I’ll take that,” she said.
“Last year I came here and I didn’t even win a match and here I am now.”
I faked it a lot because I was feeling like crap out there
Vandeweghe’s win advances her to just a second career slam quarter-final, where she will play Spanish seventh seed Garbine Muguruza.
After the win, the brash American revealed her overly confident persona had been an act.
“I faked it a lot because I was feeling like crap out there… what do they say, ‘fake it until you make it’?,” she said.
“When you play tough players, like you will in later rounds of tournaments, you can’t be showing you’re struggling or not confident.”
With a glut of top seeds falling early, ageless champion Roger Federer is suddenly – and extraordinarily – the new men’s favourite.
The 35-year-old father of four is contesting his first official tournament in six months following a a career-threatening injury-enforced layoff.
But after backing up his third-round schooling of 10th seed Tomas Berdych with a 6-7 (4-7) 6-4 6-1 4-6 6-3 defeat of fifth seed Kei Nishikori last night, Federer now has the backing of bookmakers around the world.
The Swiss great’s vintage form and the shock exits of Sir Andy Murray and six-time champion Novak Djokovic – marking the first time in 15 years the top two seeds have bowed out – have conspired to have Federer installed as Open favourite at the tournament’s halfway point.
Such a scenario was unthinkable a week ago as Murray, the newly-knighted and newly-elevated world No.1, and Djokovic arrived in Melbourne eyeing their own special places in tennis history.
Instead, Federer – who harboured only modest expectations before embarking on his 18th consecutive Open tilt – will play Mischa Zverev in the quarter-finals tomorrow after the unheralded German sent Murray packing yesterday.
Hunting down an elusive 18th grand slam crown – five years after landing his record 17th – Federer could strike fourth-seeded countryman Stan Wawrinka or Jo-Wilfried Tsonga in the semi-finals.
The winner of the top half of the draw will likely line up against either third seed Milos Raonic or eighth seed Dominic Thiem in the final – or Rafael Nadal if the two grand slam titans can each win two more matches.
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