World number one Roger Federer returns the ball against Donald Young
World number one Roger Federer began his bid for a record sixth US Open title with a straight-sets victory over Donald Young of the United States.
The Wimbledon champion, chasing his 18th Grand Slam title, brushed aside Young 6-3 6-2 6-4.
No player in the professional era has won the US Open more than five times, a record Federer shares with Pete Sampras and Jimmy Connors.
The number one seed will face German veteran Bjorn Phau in round two.
Federer arrived at Flushing Meadows in great form, having beaten Andy Murray to win his seventh Wimbledon title, then reached the Olympic final before defeating defending US Open champion Novak Djokovic to win the Masters Series tournament in Cincinnati.
"Novak, to me, goes in as the favourite still because he's the defending champion," Federer said. "He's probably won the most titles on hard courts the last couple of years. It's where he felt most comfortable."
Young, beaten in the fourth round by Murray at last year's US Open, never really threatened an upset.
Federer made his move in the eighth game of the first set, breaking to love and then serving out to take it 6-3, and was soon a break up in the second set.
Young earned a huge cheer from the crowd when he levelled at 2-2 but the top seed soon surged away again.
In the third set, the American hung on before Federer served out for victory after an hour and 34 minutes.
Number 12 seed Marin Cilic, of Croatia, beat Australia's Marinko Matosevic 5-7 2-6 6-4 6-2 6-4, while Frenchman Gilles Simon, seeded 16th, defeated American Michael Russell 7-6 (7-4) 3-6 5-7 6-4 6-1.
A heavy thunderstorm earlier in the day had put the matches behind schedule but there was some home success for the fans to cheer, with Mardy Fish beating Japan's Go Soeda 7-6 (7-3) 7-6 (7-2) 6-3 and wins, too, for James Blake and Jack Sock.
Wildcard Sock, 19, went through when 22nd seed Florian Mayer retired with the American leading 6-3 6-2 3-2, while 32-year-old Blake defeated Slovakia's Lukas Lacko 7-5 6-2 3-6 6-3.
Japan's Kei Nishikori, the 17th seed, was a 6-1 6-2 6-4 winner over Argentinian qualifier Guido Andreozzi and there were also wins for Nikolay Davydenko, Jeremy Chardy and Marcel Granollers.