Even though he thought he could sleep late, 18-year-old United States long jumper Carl Lewis woke up at 9 o'clock. Saturday morning, 10 hours before he believed he was scheduled to compete in the Pam Am games.

This was the day he had waited for all his athletic life. His mother Evelyn had run the 80-meter hurdles in the first Pan Am Games in 1951, and both she and her husband Bill are track coaches. Lewis had been bred for this day.

Just 15 minutes later, before the sleep was out of his eyes. Lewis had begun the most frentic and memorable day of his young life. "hurry up," said U.S. Coach Jim Bush. "They've changed the rules again -- they're having qualifying trials at 10 a.m."

"But they've called those trials off twice," answered Lewis. "They just sent us another cancellation last night."

"Hurry up," said Bush, and the race was on.

When he jogged through the stadium gates to the sign-up table, the clock read 10:20 -- two minutes late.

"I was worried right away," said Lewis. "i couldn't understand what the (Pan Am) official was saying, but I know what 'No, no, no, no,' means. He was getting his point across real strong."

From 10:02 until 3:30 p.m., Lewis officially was disqualified from the long jump, despite the fact that those 10 a.m. trials never were actually held.Only 11 jumpers showed up and anything fewer than 15 does not necessitate trials. Everybody is in the final.

For over five hours, as United States coaches argued, Lewis "tried to look on the whole thing as a learning experience. I kept telling myself that despite all the work I'd done to get here, it wasn't anything really drastic. I just turned 18 on Sunday."

It was adults, like Lewis' mother, who fought back tears, and coaches like Bush, who were mad, pointing out that Lewis, rather than being late, had arrived in San Juan eight days early and had been officially notified twice in writing that the trials would not be held -- as in fact they were not.

True to form, United States coaches beat on heads until Lewis was reinstated. A Canadian javelin thrower, by contrast, earlier gave up a somewhat similar protest and flew home.

Once allowed to jump, Lewis delivered the bacon -- leaping a personal best of 26 feet 8 inches on his last try to win a bronze medal. He was only two inches behind the gold medal jump.

"I love it . . . I'm really satisfied," glowed Lewis. "Last year, I couldn't even jump 25 feet. Now I win a medal in the Pan Am Games." CAPTION: Picture, U.S. sprinter Harvey Glance, right, Looks at Sivio Leonard of Cuba, who won Pan Am gold medal in 100 meters. AP