The top-seeded American, whose buildup to the season’s final grand slam had been interrupted by an abdominal injury, showed no signs of rust as he eased to victory in just over an hour to book his place in the last eight.

Roddick, the 2003 US Open champion, will next meet seventh-seeded Argentine Juan Monaco who hammered Japan’s Kei Nishikori 6-0, 6-3.

In other matches, fourth-seeded American John Isner powered past Finland’s Jarkko Nieminen 7-6 6-2 while third seed Alexandr Dolgopolov of Ukraine had to work hard for a 6-4, 1-6, 7-6 victory over 14th-seeded Bulgarian Grigor Dimitrov.

“It took me a while to get used to how he was playing,” the big-serving Isner told reporters. “From 4-4 in the tie-break, that’s when I really kicked up. I was kind of on my way from there.

‘I held serve comfortably today and that just puts so much pressure on my opponents. I’m very fortunate to have my serve.”

Ninth-seeded Ukrainian Sergiy Stakhovsky pulled off the biggest surprise in the third round, upsetting fifth seed Nikolay Davydenko of Russia 6-4, 6-4.
 
Li Na advances to New Haven quarters

In New Haven, Connecticut, Li Na of China had to battle from behind in each set Wednesday to beat Russia’s Maria Kirilenko 6-4, 7-6 (4) in the second round of the New Haven Open, the final WTA tournament before the US Open.

The French Open champion had trailed 3-1 in the first set and 4-1 in the second, before securing the straight-set win and a berth in the quarterfinals, where she will meet Russian Anastasia Pavlyuchenkova, who downed Italy’s Roberta Vinci 6-2, 6-4.

Marion Bartoli, seeded foruth, also progressed to the last eight, beating Czech Klara Zakopalova 6-2, 2-6, 6-1. The Frenchwoman will next face another Czech: qualifier Petra Cetkovska.

Unseeded Spaniard Anabel Madinah Garrigues moved into the quarters, overcoming a knee injury to win 6-2, 7-6 (5) win over Elena Vesnina of Russia. He next opponent will be Italian Francesca Schiavone.

Li, the first Asian to win a Grand Slam event, has beaten Kirilenko four of the five times they have met. But, she said, the Russian, like most of her opponents since the French Open, seemed to be a bit more focused this time.

“Everyone thinks different,” she said. “Before (it was), `Oh, OK, I beat her.’ But now, if they win, `Oh, I beat a French Open champion.’ They are even more excited.”

Li took the first set after breaking Kirilenko in the seventh game, which went to deuce four times. She also broke Kirilenko in the seventh game of the second set to get back on serve. She then won four straight points in the tiebreaker for a 6-2 cushion.

She will next face another Russian, Anastasia Pavlyuchenkova. The eighth seed also won in straight sets, beating Roberta Vinci of Italy, 6-2, 6-4 after jumping out to a 5-1 lead early.

Madinah Garrigues, looking for her third tournament title this season, was in charge throughout against Vesnina. But she failed to convert on three match points while up 6-5 and serving for the second set. Vesnina hit a passing shot to save the third match point, and Madinah Garrigues sat on the court and grabbed her right knee.

After a brief medical delay, Vesnina broke serve to force the tiebreaker.

But Madinah Garrigues said she was able to take advantage of a gusting wind, which was at her back at the end of the tiebreaker, and gut out the win. She said she might have retired from the match if she had lost the second set.

“I was thinking of that,” she said. “But I was lucky. I won the tiebreaker and I won the match.”