KEY BISCAYNE, Fla. -- He's 32 years old and a new father, past his prime but not ready to retire.

So there was Todd Martin, out there in the sweltering sunshine Wednesday, grinding out a victory in a mostly empty stadium on the first day of the Nasdaq-100 Open.

Martin beat Mariano Zabaleta 6-4, 6-4 for just his second victory in four matches this year. The relative inactivity has dropped his ranking to 114th, the first time he has been out of the top 100 since 1992.

But that didn't matter against Zabaleta, an Argentine ranked 36th.

"I've learned that rankings mean very little,'' Martin said. "Rankings get you into tournaments, they get you seeded, they might get your name in the paper. But it's really just evidence of what you have accomplished in the past year. It has nothing to do with what you're able to accomplish tomorrow. Or today.''

The biggest thing Martin has accomplished this year is becoming a father. His wife, Amy, gave birth Jan. 21 to a son, Jackson.

Fellow thirtysomething Pete Sampras hasn't played since becoming a father in November. Martin skipped the Australian Open in January but decided to rejoin the tour, accompanied by his wife and baby -- at least for now.

"We don't intend to raise our child as a gypsy,'' Martin said. "I'm in constant introspection about my career and what the next step is and how long the step I'm taking will last. I have no preconceived notions.''

With all seeded players receiving a first-round bye, Martin was the biggest name in action on a humid, 90-degree afternoon, a record for the date.

Americans Taylor Dent, Jan-Michael Gambill, Robby Ginepri and Mardy Fish joined Martin in the second round. Dent beat 1999 champion Richard Krajicek 6-4, 6-3. Gambill rallied past Stefan Koubek 2-6, 6-3, 6-2, and Fish recovered from a slow start to beat Adrian Voinea 0-6, 6-4, 6-2. Ginepri beat Wayne Arthurs 7-5, 6-3.

Play began as scheduled despite a looming U.S. war against Iraq, and Martin said taking the court was the right thing to do.

"It's important that we all understand the gravity of the situation in the Middle East, the predicament and the challenge that is ahead of our military forces and others,'' he said. "But it's important that we go about our business and show them that our world's not stopping because of a conflict.''

Martin next plays Andrei Pavel for a berth in the third round. He has made it that far only twice in seven previous appearances at Key Biscayne.

But Martin could get hot if the weather stays that way. It made the balls faster and less fluffy, which suits his attacking style.

"Typically, I haven't played well here,'' Martin said. "I would say today the conditions are about as good as they can be for me. It's nice when I'm here and feel like the ball's not one of the larger citrus fruits.''