You don't know Charlie Mueller, the jockey. You know Shoemaker and Cordero, Pincay and Velasquez. They are the big boys among the little brave men who ride thousand-pound horses in traffic. Their horses win the Kentucky Derby. You don't know the Charlie Muellers who ride horses so slow they need search parties to help them get home.

This morning's sun worked against the night's chill outside Barn 41, where you saw Charlie Mueller leaning against the concrete block barn wall. Steam rose out of straw pitchforked from the stalls. The rising steam carried the unmistakable fragrance of the race track, and you asked Charlie Mueller, knowing the answer, if he thought this was as good as it gets.

"My wife is coming to town tomorrow," Charlie Mueller said. "I wish she had been here all week. This is exciting. All those years, watching the Derby on television, I wondered what it'd be like to be here with the big boys. I love it. It's been a long time coming."

You ask him his story. You know about Shoemaker, how the great man weighed 2 1/2 pounds at birth and the doctor gave up and his grandmother put him in a shoebox and kept him warm in the kitchen oven. You know Shoe has won 8,000 races. So you ask Charlie Mueller how many he has won.

"I don't know," the jockey said. "Enough."

There will be 20 horses in this Derby, with a thousand dreams running, and you see in Charlie Mueller how happy a person can get just winning enough to keep feeding his wife and little daughters, winning enough to keep on dreaming. The jockey's face, the mask of his job, is sharp edges and creases at the corners, the kid's glow turned to leather by the wind of 3,000 races and 3,000 workouts at dawn.

Nobody ever told Charlie Mueller anything would be easy. Maybe that's why he's so happy here. He's 34 years old, but he never rode a horse until he was 22. He grew up in the outback of Texas, outside Houston, and he liked pouring down beer more than he liked working.

He went to welding school, and he worked construction, and he cut grass along highways. This was in the '60s during Vietnam. So, what the hell, Charlie Mueller, all 5-foot-2 and 105 pounds, answered the draft when he could have lost two pounds and been deferred.

"I didn't have anywhere else to go," Mueller said. The bad guys in Nam threw rockets at Mueller's helicopter base, where he did mechanic's work. "Rockets is all. No shooting. Just rockets."

Back in Texas, now 20 and drifting, Charlie Mueller took a job on a farm at Hufsmith, population 1,600. Baled hay, fixed fence. He'd never been on a horse when the boss, Bubba Cascio, said, sure, if you want to, Charlie, get on that nag. Just walk him until you get the feel of it in a few days.

Mueller told the story with a smile warmer than the sun. If he wins 8,000 races and three Kentucky Derbies, the way Shoemaker has, Charlie Mueller yet will remember Bubba Cascio telling him to walk the nag.

"I walked him for a couple minutes," Mueller said.

The jockey's voice rose.

"Then I tore a limb out of a pecan tree, clipped his rear end and went on with him."

Laughing now.

"I stood up on him, I rode him like I knew what I was doing."

A race rider was born, a race rider 22 years old, just out from under rockets in Vietnam, drifting in search of what he was. Charlie Mueller was a race rider. "It felt right. I never tried it before because in Texas nobody talked about being a jockey. In Kentucky, I'd have started when I was 16 and maybe I'd be one of the big boys now."

For $85 a week, Charlie Mueller worked on Cascio's farm and at his racing stable at Ruidoso, N.M. He galloped horses in the morning. Blowing paper spooked his horse once, causing it to throw Mueller into a steel pole: 35 stitches, eight teeth. He was back riding in a week. Race riders ride races. To pay the rent, this race rider worked as a plumber in the afternoons.

On May 27, 1972, he won his first race.

"Nobody wanted to ride that horse because he had bucked knees. But I wanted to ride. I rode everything I could get on."

The bullrings and bush tracks of New Mexico were his home for eight years, those little circles of hellish risk where you might earn $25 a day. So you ask Charlie Mueller what it was like and the answer comes back to you in three Texas-drawl syllables.

"Dis . . . gust . . . ing."

You laughed, but Mueller didn't. "You couldn't make any money and nobody thought I could ride. I hadn't been on any good horses, so how did anybody know? It took me two years and three months to lose the bug."

The bug is the asterisk that marks apprentice riders. It stays until he wins 45 races. Then Mueller began to win a lot: he was the leading rider at Ruidoso Downs in '78, and a leader at Sunland Park near El Paso in 1977-78-79.

The last three years he has worked in Louisiana, a step up, and when Explosive Wagon won at 1 1/16th miles this spring, Mueller said, "Uh-oh, I got me a big horse."

Still, nobody thinks Mueller's ride can win the Derby. He will be 30-1 in the track odds as part of a five-horse betting entry. When you've been under rockets and under kitchen sinks and on bucked-knee nags, it doesn't matter.

"This," Charlie Mueller said, squinting into the Kentucky sun, "is it."