John Isner, fresh off a seventh ATP title, fired 19 aces Wednesday to beat Alex Kuznetsov 7-6 (7/2), 7-6 (7/4) at the ATP and WTA Washington Open.
Eighth-seeded America-n Isner, who won last week at Atlanta, advanced to the Round of 16 at the $1.76 million hardcourt event before rain washed out most of the day’s matches.
That included tournament openers for Argentine top seed Juan Martin Del Potro, the 2009 US Open champion and a two-time Washington winner, and second seed Kei Nishikori, who received first-round byes.
Two other second-round matches were halted, with South African seventh seed Kevin Anderson leading Australian qualifier James Duckworth 6-3, 3-6, 5-4 and German third seed Tommy Haas leading US qualifier Tim Smyczek 3-6, 7-5, 1-0.
The total washouts for Nishikori, ranked a career-best 11th this week, and Del Potro mean they will have to win five times in four days to take the title.
On the women’s side, Germany’s Andrea Petkovic upset sixth-seeded compatriot Mona Barthel 6-2, 6-2 to reach the last eight in the only match completed.
Azarenka victorious on birthday
In Carlsbad, top-seeded Victoria Azarenka, playing for the first time since an injury withdrawal from Wimbledon, celebrated her birthday with a WTA win.
Australian Open champion Azarenka, ranked third in the world, cruised into the quarter-finals with a 6-2, 6-3 second-round victory over former French Open champion Francesca Schiavone of Italy.
“Just going on the court and competing was so much joy for me,” said Azarenka, who turned 24 on Wednesday.
Former Wimbledon champion Petra Kvitova, the third seed, also eased into the quarters, beating Britain’s Laura Robson 6-1, 6-2.
Fourth-seeded Roberta Vinci of Italy advanced with a 6-4, 6-2 win over American Bethanie Mattek-Sands.