Champion Angelique Kerber stunned in first round by brilliant Naomi Osaka
Naomi Osaka v Angelique Kerber

Champion Angelique Kerber stunned in first round by brilliant Naomi Osaka

Defending champion Angelique Kerber is out of the US Open after suffering a stunning 6-3 6-1 defeat to world number 45 Naomi Osaka in the first round.

World number six Kerber fell to another miserable defeat in suffering an afternoon to forget under the roof on Arthur Ashe.

It was the 19-year-old Osaka's first win over a player in the top ten of the women's game.

The Japanese teenager was well worth the victory, hitting 22 winners compared to only nine by Kerber, whose form has nosedived a year after she became world number one by winning the Australian Open and the US Open a year ago.

"I played good today, and I hope to carry that onto my next match," said Osaka.

The last defending champion to lose in the first round at Flushing Meadows was Russian Svetlana Kuznetsova in 2005.

"I was always believing until the end that I could turn around the match, because I turn around a lot of matches," Kerber told a news conference.

"She played good, especially also at the end of the match. I'm always trying to go for it when I had the chance."

Kerber barely got that chance as Osaka, who last year had been described by 23-times grand slam champion Serena Williams as 'very dangerous', put her on the back foot with her aggressive play.

"Today she went for it. I think she took the chances, and she played a very good match. But for me it was for sure not the best day and not the best match."

Osaka, who grew up in New York, broke for 5-3 and sealed the opening set with a sizzling winner down the line under the closed roof at Arthur Ashe Stadium.

World number 45 Osaka broke in the first game of the second set and continued to pepper the court with winners to hold for 2-0.

Kerber had four break points but failed to convert any as Osaka completed her demolition job to claim her first career victory against a top-10 player.

She next faces either Swedish qualifier Rebecca Peterson or Czech Denisa Allertova with a potential fourth-round clash against French Open champion Jelena Ostapenko looming.

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