Andy Roddick of the US hits a backhand return to Jose Acasuso of Argentina during their second round match on the fourth day of the 2007 US Open tennis tournament in Flushing Meadows, New York, USA
"I don't think you like winning matches like that," said 2003 winner Roddick, who improved to 3-1 in career birthday matches at Flushing Meadows.
"I felt (after the first set) that I was starting to play okay and make returns and react," he said. "But at the end of the day, your goal is to get through and to give yourself a chance to play in the third round.
"I'm going to be able to, so it's all right."
Acasuso, ranked 70th, began feeling his knee in the second set after winning the first. As Acasuso's form slid downhill, Roddick's stock rose, with the seed managing a dozen aces in the abbreviated effort.
Even after dropping the first set, fifth seed Roddick said he was unworried about his prospects. "I felt like I was hitting the ball okay. The points weren't going terribly. I didn't feel real uncomfortable out there.
"I knew that after the first set I could turn it into a long day."
Number four Nikolay Davydenko made his move to the third round, dashing the upset hopes of German Nicolas Kiefer 6-2, 6-2, 6-2.
Ninth seeded Czech Tomas Berdych advanced over Italy's Simone Bolelli 7-5, 6-3, 6-3 while American teenager Donald Young got a free ride at his career-first Grand Slam when 13th seed Richard Gasquet withdrew due to illness prior to their match.
South Korean Hyung Taik put out 14th seed Guillermo Canas 7-5, 7- 5, 6-3, eliminating the man who beat Roger Federer twice in as many events on spring hardcourt.
Andy Murray sealed his comeback from more than three months of wrist injury agony with a 5-7, 6-3, 6-1, 4-6, 6-1 defeat of Jonas Bjorkman.
The British number one further polished a game, which had been dulled by a dozen weeks out of ATP action followed by two poor comeback weeks at August Masters Series events in Montreal and Cincinnati.
The former top-10 player who won the Open juniors in 2004 claimed matches for the first time in his comeback as he stopped 1997 semifinalist Bjorkman, 15 years his senior.
"He's in really good shape for his age," the 20-year-old said. "He's got a lot of experience.
"I knew it was going to be a difficult match, he changes his tactics quite a lot."
Murray's win was his sixth at the event in three years.
The Scot gave his wrist a solid workout with more than three hours on court, firing 16 aces and breaking on 10 of 19 chances.
"The wrist is fine, I didn't feel it once during the match."
Wokmen's holder Maria Sharapova raced past inexperienced Australia Casey Dellacqua 6-1, 6-0 with an effortless 30 winners and six breaks of serve against the number 90, a 22-year-old playing the New York main draw for the first time.
2004 winner Svetlana Kuznetsova led a Russian trio ahead, pacing fellow seeds Anna Chakvetadze and Nadia Petrova, the number six and seven.
"It feels pretty much a long time ago, I try to focus," said Kuznetsova of her 2004 triumph after overcoming feisty Frenchwoman Camille Pin 6-3, 4-6, 6-0.
"It's a new era, it's been three years, it feels long ago."
Kuzy also returned to her comfort zone as she played for the first time since her trophy run on the Ashe showcase court with its 20,000 capacity.
Chakvetadze, winner of back-to-back titles this summer on hardcourt in the US, defeated Australian veteran Nicole Pratt 6-3, 6- 4. Petrova ousted compatriot Anastasia Rodionova 7-5, 6-1.
1997 winner Martina Hingis defeated Pauline Parmentier 6-2, 7-5.
The Swiss player took a three-year "retirement" from 2002 to 2006 and has now been a fixture on the WTA for 19 months. But her current season has been compromised by inflammation problems, which have affected her hip and back.
The New York fortnight so far shows that the former child star is returning to her former level. She now stands 43-8 at the event as she plays for the 10th time.
The 16th seed said her level dropped a touch due to accumulated stress at the most hectic of the Grand Slams.
"That's the reason why probably top players try to cut down the hours out here. It also it took us an hour to get out here this morning," she said. "It's just all these little things."
Hingis was joined as a winner by fellow Swiss player Patty Schnyder, the number 11 who beat Severine Bremond 6-3, 6-0. Nicole Vaidisova, seeded 13th, stopped Italian Flavia Pennetta 6-2, 7-6 (7- 0)