But Saturday night, after she had easily dispatched Olga Govortsova, 6-1, 6-2, to advance to the final 16, she said her run to top form, to the sixth-ranked player in the world, began right here last year when she made it to the semifinals and lost to Samantha Stosur, the eventual champion. This season Kerber has won 52 matches on tour, not counting Fed Cup and the Olympics, the most of any player.
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"Yes, for sure, it's special to be back here," said the 24-year-old German. "Because last year everything starts here. I mean, nobody knows me one year ago. Right now I also have a little bit of pressure. So it's for sure different than last year. I have a lot of good memories from last year."
On Thursday night Kerber ground out a 2:45 win over Venus Williams at Ashe Stadium, overcoming both a former champion and the crowd that was vociferously on her side. She did it with her chief weapon -- court coverage -- and with steely resolve that had not always been her forte.
It was her second appearance at Ashe in the Open, the first one against Venus' sister Serena in 2007. Back then she was little more than a sacrificial lamb and lost in two sets, though she was not steamrollered. There was considerable difference between the teenage pro then and the seasoned professional now in search of her first Grand Slam title.
"If I played Serena years ago there, that was my first or second year on the WTA," Kerber said. "Right now I'm feeling very well. It was very good experience for me to play two days ago here on Ashe against Venus."
That match against Venus Williams, which pushed her record to 19-2 in three-setters this season, was the sort that conditions a player to perform on the big stage of Grand Slam events.
"I'm not thinking about to win a Grand Slam right now. I'm looking round to round," Kerber said. "It was an unbelievable feeling out there. I'm happy I won this match because it was very tough and close match physically and mentally."
In other matches involving seeded women players, No. 2 Agnieszka Radwanska beat Jelena Jankovic, 6-3, 7-5. Sara Errani, Kerber's next opponent, beat Olga Puchkova, 6-1, 6-1. Maria Kirilenko, the 13th seed, fell to the unseeded Andrea Hlavackova, 5-7, 6-4, 6-4. Roberta Vinci, No. 20, knocked off Dominika Cibulkova, 6-2, 7-5.