WASHINGTON (AP) -- Andy Roddick withdrew from the Legg Mason Tennis Classic on Monday because of a strained back, but said the injury shouldn't prevent him from being at full strength for the U.S. Open.
Roddick strained the lower left side of his back following a second-round victory over Scott Oudsema at the Countrywide Classic in Los Angeles last week. He went on to reach the finals of that tournament, losing to James Blake.
The injury hindered Roddick throughout a 30-minute practice Monday.
"I could still feel the injury and I guess where the injury actually is," said Roddick, who won here last year and in 2001. "I have been advised that it is in an easy place to re-aggravate. I could still feel it out there today, and I didn't feel like I was well enough to practice tomorrow."
Roddick's first match was scheduled for Wednesday against Janko Tipsarevic of Serbia. Jan-Michael Gambill of the United States will replace Roddick in the draw.
Roddick said that he hopes to play next week in Toronto and then the following week in Cincinnati in preparation for the U.S. Open, which begins Aug. 28.
Play began at the Legg Mason Classic on Monday with Wesley Moodie beating California teenager Sam Querrey 2-6, 7-6 (4), 7-6 (6).
The 6-foot-6 Querrey dominated his South African opponent with 19 aces in the first set, winning 82 percent of his first-serve points. However, Moodie rebounded in the second set and avoided the upset.
In other opening round matches, Russian Marat Safin defeated countryman Igor Kunitsyn 6-3, 7-6 (6); American Kevin Kim defeated Oudsema 6-1, 6-3; Ryan Sweeting of the United States defeated countryman Justin Gimelstob, 7-6 (7), 6-2, and Andrea Stoppini of Italy downed American Paul Goldstein 6-3, 6-2.