Michael Phelps isn't old enough to drive, but last night he swam fast enough to get to Sydney, Australia.

A 15-year-old from Towson, Phelps will be the youngest male to represent the United States in Olympic swimming since 1932. Fourth with 50 meters to go, he charged home with poise that belied his youth and finished second in the 200-meter butterfly at the U.S. trials."At first, I couldn't believe it," said Phelps, of the results that flashed instantaneously on the scoreboard at the Indiana University Natatorium. "I thought I saw it, and then I had to take off my goggles to really see."

Believe it. Phelps will be late for the start of his sophomore year at Towson High, but he'll return with knowledge in international relations and history.

Ralph Flanagan was 13 when he swam for the Americans at the Los Angeles Olympics in 1932. How long ago was that? America was mired in the Great Depression, Babe Ruth was still in his prime and Olympics swim star Johnny Weissmuller passed on a chance at his third Games to sign a movie deal that made him Tarzan.

It being the dawn of a different millennium, Phelps strode out of the locker room for the parade of finalists with East Coast rapper DMX booming on his portable CD headset.

Over the past two days, Phelps became more than just another prodigy from the North Baltimore Aquatic Club. Last year, his best time in the event was 2 minutes, 4.68 seconds. In March, he broke two minutes for the first time. He lowered his personal best in each of the three rounds here, and last night's clocking of 1:57.48 made him the fourth-fastest American ever.

Phelps' time placed him among the top 10 in the world this year. He was less than a second behind Tom Malchow, the world-record holder who touched in 1:56.87.

He has experienced a huge growth spurt this year, adding four inches to get to 6 feet 3. Phelps may be even taller by the time he competes at the Olympics, and it is premature to discount his medal chances in Sydney. There will be none of the make-or-break pressure he faced here, where only the top two finishers qualify for the Games in individual events.

Phelps made some rookie mistakes in Friday's semifinals. He was late removing his warm-ups and had an awkward turn at 100 meters, but he turned in what seemed to be a flawless swim last night.

Jeff Somensatto of Annandale, Va., and Auburn University, his main competition for second place, pushed the early pace, and Phelps settled into fourth.

Phelps stayed there until the final turn, then flashed through the final 50 meters in 30.02 seconds, faster than anyone in the eight-man field. He overcame Somensatto and Steve Brown with about 20 meters left, and had a cushion of .59 second in his quest for the runner-up spot.

"That showed a whole lot more than 15 years worth of maturity," said Bob Bowman, Phelps' coach at NBAC. "The last thing I told him before he left for the announcements was to keep coming on that last 50 [meters] no matter what, and that's exactly what he did.

"Michael's always been good at getting mentally prepared for races. He has a structured relaxation program and practices a visualization technique. I think he had already replayed that swim 100 times in his mind."

Phelps said "I had no idea where I was" coming off the final turn, but Malchow can see him glaring in his rearview mirror.

"He [Phelps] didn't get caught up in the hype," Malchow said. "That's a tremendous credit to him. He stuck to his game plan. He didn't get rattled."

Malchow has six of the 10 fastest times in history, and was the Olympic silver medalist in the event four years ago. He was a few weeks shy of his 20th birthday in Atlanta, where he was the youngest member of the 1996 men's team.

"He's awesome, way ahead of where any other flyer has been at his age," Malchow said on the pool deck. "I may have to retire sooner than I thought. He's exactly me four years ago. He doesn't know how much his life is going to change, but it's going to change real soon."

Minutes later, Phelps was the wide-eyed subject of the first news conference of his career. He elaborated - as best a euphoric 15-year-old boy can - on the sacrifices he has made to place himself among the world's best swimmers.

"I had to pass up a lot of things with my friends," Phelps said. "At the time, I was upset, but right now I'm happy that I passed up things like late-night movies and parties."

Like all swimming Olympians, Phelps had his palm painted red, white and blue, and left his handprint on a poster. En route to drug testing, he stopped to sign autographs. Most of the seekers were little girls.

Phelps will return to Baltimore later this week, and it will be a brief layover. The U.S. Olympic training camp opens next weekend in Pasadena, Calif. Phelps will train there for two weeks, then depart for Sydney Sept. 3.

Before he finalizes his travel plans, Phelps planned to be back in the pool this morning, for the preliminaries of the 200 individual medley. He will leave the IU Natatorium with sweeter memories than he took in 1996.

Four years ago, his sister Whitney was the No. 1 seed in the 200 butterfly, but was unable to convert her credentials into a spot on the U.S. team. Michael was in the stands, and hugged his mother, Deborah, as she cried over that setback. His family was here again en masse, and Whitney made her way down to the diving pool where competitors warm down to congratulate her brother.

"I was so psyched, but I just wanted to get this over with," Whitney said. "Michael is incredible."

For the second time in four years, Phelps tears were shed at the IU Natatorium. This time, it was a spigot of joy.