Now, the jockey who began riding as a boy in Chile is aboard Funny Cide and on the brink of giving racing its first Triple Crown winner in 25 years.
"It's going to be the best ride of my life," Santos said. "I think he's going to get a victory."
A win in Saturday's Belmont Stakes would be the pinnacle of a turbulent career that seemed to hit bottom five weeks ago when Santos was accused of cheating to win the Kentucky Derby.
"I was very surprised," he said. "It's not fair."
A photograph seemed to show he might have been carrying something in his hand besides his whip when he won the Derby. After a two-day review, Churchill Downs stewards determined Santos had done nothing wrong.
The jockey didn't exactly take to Funny Cide at the outset. His agent asked him to exercise the New York-bred gelding for trainer Barclay Tagg, and Santos wanted no part of it.
"Do I have to work a horse for that grouchy guy?" Santos replied.
His agent insisted, so Santos worked out the horse and thought Funny Cide had a future.
Now he's many furlongs from his South American boyhood, when he first got involved with horses at 8. The bloodlines already were there: His father and three of his seven brothers were jockeys.
Santos rode his first race at 14, and three years later took off on his own for Colombia. That's where he found trouble.
"I was making a lot of money. I had some friends. I went drinking. We went out to discotheques, and before you know it, you're doing cocaine," he said. "I went like that for 5½ years."
Santos rode during the day and burned his money at night. The wild times ended in 1984 when he got off a plane in Miami.
"I put my right foot on the ground and said, `That's it. It's a new start,"' he said.
He claims to have quit cocaine cold turkey.
"I never went back because I knew how bad it was," he said.
The first few months were the hardest. He wanted to make money to send home, but he rode only one horse every few weeks and usually finished second or third.
Desperate to win, he rode with a fury. One day, he finished first by seven lengths. Santos' joy was short-lived. An inquiry was posted and stewards reviewed the race.
They decided his chaotic style had bothered five other horses, and he was suspended for three weeks.
More suspensions followed, but Santos eventually calmed down. He led the nation in earnings during a four-year stretch in the late 1980s.
In 1992, he broke his right arm and collarbone and cracked his hip. Two pins and 14 screws were implanted in his arm, which is pocked by scars. He was laid up the rest of the year.
He knew he couldn't quit, not with just a sixth-grade education to fall back on.
"That's my job and I know how to do it," he said. "You give me a hammer and I don't know what to do with it."
At the same time, his first marriage was in trouble. It eventually ended in an expensive divorce.
In 2001, Santos broke his right wrist in another accident, sidelining him for five months. By then, he had married again, this time to Rita, a Panamanian whose father and brother were jockeys.
"She keeps me happy," he said.
Santos hasn't been to his Hollywood, Fla., home since his 42nd birthday on April 26. Even then, he was there to ride. As a present, Rita gave him a silver bracelet he had coveted in the belief it might ease his arthritis.
"That controversial thing," as Rita refers to the bracelet, was part of the Derby uproar. Santos still wears it, although Rita thought he should throw it away.
The couple has four children, ages 5 to 15, and Santos has a teenage daughter and son from his earlier marriage. The jockey credits Rita for taking the domestic pressure off him.
"She's the mommy and daddy at the same time, she does everything for the kids," he said.
Rita and the children live in Florida. The only extended time they spend with Santos is when he rides in Florida during the winter and when they visit him during the summer at Saratoga.
"There's times I have to put my foot down and say, `You have to get home, your children need you,"' Rita said. "When he hears that, he knows it's time to come home. Then it's like a honeymoon."
By Beth Harris