Roger Federer rolled into the third round of the US Open on Thursday while sixth seed Nikolay Davydenko lost and Japanese qualifier Kei Nishikori dumped 11th seed Marin Cilic in five grueling sets.
Swiss second seed Federer, seeking his 17th Grand Slam crown and a seventh consecutive trip to the US Open final, eliminated Germany's 104th-ranked Andreas Beck 6-3, 6-4, 6-3 in one hour and 41 minutes at Arthur Ashe Stadium.
Federer jumped ahead 5-0 in only 12 minutes, claimed the first set in 27 minutes and was seldom threatened.
"It's the perfect start," Federer said. "I played Monday, had two days off, I had another easy one physically and here I am in the third round feeling like I'm completely in the tournament."
Federer, a five-time US Open champion, will face 109th-ranked Paul-Henri Mathieu to decide a berth in the last 16 on the Flushing Meadows hardcourts.
"Body is well. Mentally obviously I'm fresh, too. I haven't played too much, so I'm really eager," Federer said. "I'm ready for tough matches coming around. It's good I'm saving myself, really, and my game is fine."
Russian Davydenko, a 2006 and 2007 US Open semi-final loser to Federer, was pounded 6-3, 6-4, 6-2 by 38th-ranked Richard Gasquet, who will next face either South African Kevin Anderson or Brazilian 26th seed Thomasz Bellucci.
Gasquet, among a record 12 Frenchmen to reach the second round, lost only seven of 52 points on his first serve as Davydenko made his quickest US Open exit since 2005.
Davydenko joined a US Open seeded scrap heap that includes No. 7 Tomas Berdych of the Czech Republic, US ninth seed Andy Roddick and Croatia's Cilic, who dropped the longest match of the week just 60 seconds shy of five hours.
"It was very humid. It wasn't easy to get oxygen," Cilic said. "I started to feel cramps in the end of the fourth set. But with that, I was all right toward the end of the match. It was just the general tiredness and exhaustion."
Nishikori, ranked 147th, fought off cramping in the hottest day of a scorching week to defeat Australian Open semi-finalist Cilic 5-7, 7-6 (8/6), 3-6, 7-6 (7/3), 6-1 in an exhausting five-hour duel.
"I was cramping from the second set but I kept fighting and fighting and got the fourth set tie-breaker. That was key for me," Nishikori said.
"It was hot but I feel good now."
Nishikori, whose run to the US Open fourth round in 2008 was his best Slam showing and the best here by a Japanese man since 1937, next faces Spanish 21st seed Albert Montanes, who beat Australian Carsten Ball 6-4, 6-3, 6-1.
Serbian third seed Novak Djokovic was set to face Germany's Philipp Petzschner in a night match at Arthur Ashe Stadium.
Swedish fifth seed Robin Soderling reached the third round in straight sets as well, dumping American Taylor Dent 6-2, 6-2, 6-4. The French Open runner-up will play Dutchman Thiemo de Bakker next.
"I'm pretty confident. I know I can do well when I play well," Soderling said. "But you need to play well. No one can play well every match. So anything can happen. I can lose first round. I can go on really deep as well."
US 19th seed Mardy Fish, who won two titles in July and was runner-up at Cincinnati last month, eliminated Uruguay's Pablo Cuevas 7-5, 6-0, 6-2.
Next in Fish's path is France's Arnaud Clement, who led 6-3, 5-5 when Argentina's Eduardo Schwank retired with an ankle injury.
Fish said he feels like he can crack the world top-10 next year and is confident he could win a possible fourth-round match against Djokovic.
"I've never put myself in position to be a guy who is talked about at a Grand Slam," Fish said. "I'd love another crack at a top-5, top-10 player in a Slam. I've beaten a couple but not deep into a tournament.
"Getting myself in position to play a Djokovic or Davydenko, I certainly feel like I can win."