Juan Carlos Ferrero became the first seeded casualty at the US Open after he was beaten 6-3 6-4 6-4 by fellow Spaniard Feliciano Lopez in the first round on Monday.
The 21st seed, runner-up here in 2003, was outplayed throughout by Lopez, who will now play Russian Igor Andreev.
"I served so badly today," Ferrero said.
"The balls here don't help me because I like to hit with a lot of spin but when you hit the ball it's like they are dead. If you can serve big and hit the ball flat, it's better."
The only time Ferrero looked like making a fight of it was when he recovered an early break in the third set but world number 60 Lopez broke again to seal victory.
"It's just another tournament," a despondent Ferrero said.
"I know it's a grand slam, but I lost in the second round here last year. The world is still turning."