There's a trio of Americans in the women's fourth round, because wild-card entry Alison Riske, who is ranked only 81st, eliminated 2011 Wimbledon champion Petra Kvitova 6-3, 6-0. The seventh-seeded Kvitova got her blood pressure checked by a trainer, then said afterward she had a virus and a fever.
"I've got a new confidence in myself," said Riske, a 23-year-old from Pittsburgh who is now based in College Park, Md. "I believe that I belong here."
There's no doubt the other two U.S. women who are left belong: No. 1 Serena Williams and No. 15 Sloane Stephens play each other Sunday with a quarterfinal berth on the line. Williams is seeking a fifth U.S. Open title and 17th Grand Slam singles trophy overall. Stephens is one of only three women to reach the round of 16 at every major tournament this year, and she beat Williams en route to the Australian Open semifinals.
Riske next faces Daniela Hantuchova, while other fourth-rounders set up Saturday are two-time Australian Open champion Victoria Azarenka against 2008 French Open champion Ana Ivanovic, No. 10 Roberta Vinci against unseeded Camila Giorgi in an all-Italian match, and No. 21 Simona Halep against Flavia Pennetta. The 136th-ranked Giorgi defeated 2009 U.S. Open runner-up Caroline Wozniacki, who was seeded sixth, 4-6, 6-4, 6-3 at night.
Other men reaching the fourth round: No. 4 David Ferrer of Spain, No. 8 Richard Gasquet of France, and No. 10 Milos Raonic of Canada.
Raonic, the highest-ranked man in Canada's history, does not need to worry about the same kind of expectations that players such as Isner do.
"The relief, definitely, is there is obviously a lot more pressure on Americans," Raonic said. "I'm sort of doing a lot of stuff into unchartered territories, so people are very supportive of it, whereas I feel it's a little bit unfair to the American players. Everybody is expecting Pete and Agassi to be there on the top."
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