World number ones Roger Federer and Justine Henin were in cruise control as they won their respective opening round matches to advance to the second round of the US Open tennis tournament.
Three-time defending champion Federer, seeking his 12th Grand Slam singles title, opened the year's final Grand Slam event on Monday with a 6-3, 6-2, 6-4 victory over 320th-ranked American Scoville Jenkins in 92 minutes.
"I'm happy to have won my first one. I'm happy I'm through," said Federer. "It always feels like a bit of a relief. Now I can relax a little may be."
The second round opponent for Federer is another qualifier, Paul Capdeville. The Chilean outlasted Germany's Rainer Schuettler 5-7, 6-3, 6-7 (4-7), 6-4, 6-3.
Henin, who is nursing a sore shoulder, disposed of 145th-ranked German Julia Goerges 6-0, 6-3 in just over an hour.
"I'm glad to win that way," said Henin. "I was a bit concerned the last few days with my shoulder. It's getting better but still a little scary."
Henin, seeking a seventh Grand Slam title after taking her fourth French Open title in June, next plays Tsvetana Pironkova of Bulgaria who defeated Olga Poutchkova of Russia 6-3, 6-4.
Eighth seed Serena Williams, who won her eighth Grand Slam title in January at the Australian Open, showed some rust from a long layoff due to a thumb injury but defeated Germany's Angelique Kerber 6-3, 7-5.
The younger Williams sister had not played since a Wimbledon quarter-final loss to Henin.
Reigning Wimbledon champion Venus Williams downed Hungarian qualifier Kira Nagy 6-2, 6-1 in 54 minutes.
Venus next plays Romania's Ioana Raluca Olaru, who ousted American Ashley Harkleroad 7-5, 1-6, 6-4.
Serena will next meet Italy's Maria Elena Camerin, who beat Russian Tatiana Poutchek 6-3, 7-6 (7-4).
Britain's Andy Murray, who missed Wimbledon and the French Open, made a triumphant Grand Slam return from a wrist injury by defeating Uruguay's Pablo Cuevas 6-2, 6-3, 6-0.
Russian fourth seed Nikolay Davydenko and Serbian third seed Jelena Jankovic, both 2006 US Open semi-finalists, advanced in straight sets, as did Serbian fifth seed and French Open runner-up Ana Ivanovic.
Cypriot 18th seed Marcos Baghdatis was the top-ranked player to lose on day one, losing to Max Mirnyi of Belarus 6-3, 7-5, 3-6, 7-6 (8-6). Spanish 21st seed Juan Carlos Ferrero lost to countryman Feliciano Lopez 6-3, 6-4, 6-4.