LOS ANGELES -- Fourth-seeded Andy Roddick led a trio of young Americans into the second round of the Mercedes-Benz Cup on Monday, rallying for a 6-7 (5), 6-1, 6-2 victory over Lee Hyung-Taik of South Korea.

Earlier in the day, Taylor Dent, playing for the first time since winning his first ATP Tour title at Newport, R.I., earlier this month, beat Neville Godwin of South Africa 6-3, 6-4, and Jan-Michael Gambill rallied for a 4-6, 6-2, 7-6 (7) victory over Michael Chang.

In the day's other singles match, Michael Llorda of France beat Kevin Kim 6-4, 6-4.

Top-seeded Tommy Haas of Germany and defending champion Andre Agassi, seeded second, will play their first-round matches Tuesday at the Los Angeles Tennis Center on the UCLA campus.

Roddick, idle since losing to Greg Rusedski in the third round at Wimbledon, said despite his slow start against Lee he felt like he was hitting the ball well -- even in the first set.

"I served really well, and I had chances all day on his serve, which means I was returning pretty well,'' said Roddick, who had 20 aces. "I had break points on three games in the first set. If I'd got one of those, it might have been an easy day.''

The 19-year-old Roddick won tournaments at Memphis and Houston earlier this year, but hasn't gotten past the third round in his four most recent outings.

He dismissed any talk of a slump, though, pointing out that he has improved his ranking two spots to 12th this year. He also issued a polite warning to future opponents: "This is probably my favorite part of the year, outdoors, on hard courts, on a surface I think is equal for everybody. I'm excited and optimistic about the summer.''

Gambill, No. 53 in the rankings after struggling the past four months, let two match points get away before closing out his match against Chang with a forehand volley.

Chang, No. 2 in the world in 1996, won this event two years ago for his only title in the past three-plus seasons. Chang, who has slipped to No. 106 in the rankings, is 2-13 with 11 first-round losses this season after going 16-21 last year.

"The past few years have been tough,'' the 30-year-old Chang said. "I've lost a little bit of confidence along the way. I haven't won a lot of matches, but I still have hope, I'm still working hard.''