NEW YORK - Seven-time Grand Slam champion Venus Williams made her second consecutive US Open second-round exit as German sixth seed Angelique Kerber ousted the American 6-2, 5-7, 7-5, early on Friday morning.
The loss made this the first year in Williams' pro career, which began in 1997, that she has not gone past the second round in any Grand Slam tournament.
"Losing a match like this isn't a lot of fun, but that's sport," Williams said. "All I had was fight because I didn't play well."
Kerber, a 24-year-old left-hander who advanced to the semi-finals last month at Wimbledon and at last year's US Open, reached a third-round date with Olga Govortsova of Belarus, who beat British qualifier Johanna Konta 2-6, 6-2, 7-5.
"It's unbelievable," Kerber said. "I had great memories from last year and the match was so tough and so close.
"Venus won so many Grand Slams and I'm so happy to beat her in New York. It's an amazing feeling to play here in a night session."
Kerber improved to 19-2 in three-set matches this year, helped by 16 double faults and 60 unforced errors from Williams.
"I was trying hard but I was making errors everywhere," Williams said. "I made 60 errors. It's hard to win a match like that. I was fighting her and me."
Williams, whose most recent major title came in 2008 at Wimbledon, missed a chance to avenge a third-round loss to Kerber at the London Olympics.
Kerber, who had five double faults and 25 unforced errors, also beat Williams' sister Serena in a Cincinnati quarter-final to snap the 14-time Grand Slam champion's 19-match win streak that included Wimbledon and Olympic titles.
"I just tried to play my game plan, fighting every point to the last," Kerber said.
"It's amazing that I've won so many third sets in this year. I will try to stay focused and continue this in the next months."
Williams, ranked 46th, battles an auto-immune ailment that saps her energy. She has not won a title since Acapulco in 2010 and has not lifted a US Open trophy since her back-to-back crowns in 2000 and 2001.
"If I could make two more shots I probably could have won that match," said Williams. "I was extremely aggressive but it's hard to be aggressive when every shot you go for goes out. It's hard to find that balance.
"I'm not getting destroyed out there. I have to find the answer inside myself."
In the last set, Williams obtained the first break-point chance in the sixth game and capitalized with a forehand winner for a 4-2 lead, inspiring cheers of "Let's Go Venus" from the night crowd at Arthur Ashe Stadium.
"It felt nice to have that support no matter what," said Williams, calling it her best backing ever at the main court. "I waited my whole career to have this moment."
But Kerber nailed a lunging forehand volley winner in the next game to break back at 3-3 after Williams sent a forehand long.
Williams denied Kerber on a break point in the ninth game but surrendered a break when she swatted a forehand long in the 11th game and Kerber held serve to finally end matters after two hours and 45 minutes.
"I started very well but she was fighting in the second set and played great shots and I couldn't do nothing," Kerber said. "In the third set I was fighting on every point and concentrating on my game... it's amazing that I won."
Kerber, 3-1 all-time against Williams, had not won a night match at the US Open before, especially not one that followed a men's night match.
"It was late but for her it was the same," Kerber said. "I just tried to focus on my game right now and not thinking about what time it is."
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