Scott Lake wins more races than any trainer in America, but his success hasn't earned him much chance to train top-class runners.

Lake is regarded as an astute wheeler-dealer who claims horses aggressively and moves them from track to track as if they were pieces on a chessboard. He is known as a brilliant manager capable of seeing a far-flung operation with horses stabled in Maryland, New York and Pennsylvania. But owners don't seek him out when they want a trainer who can develop a young prospect or manage an expensive horse judiciously. As a result, Lake has never won a race more important than a Grade III stakes.

Today, however, he will have the chance to win the biggest race of his career when he saddles the favorite, Thunderello, for the Grade I Frank J. De Francis Memorial Dash at Laurel Park. He earned this status when he finished second in the Breeders' Cup Sprint, and in the process he enlarged his trainer's reputation. Lake knows what to do when somebody entrusts him with a good horse.

Like most owners, Charles Mady initially contacted Lake because he wanted to buy a claiming horse. A 32-year-old lawyer from Northville, Mich., Mady said, "I'm a numbers guy, and nobody has numbers [as a trainer] like he does." The two men agreed that Mady would study the Daily Racing Form and pick a horse he wanted to take, and that Lake would inspect the animal's physical condition before making the claim. After Lake rejected 10 of his suggestions, Mady observed that almost all of the horses had run poorly. Finally he said, "I'm giving up on claiming. Why don't you find me a 2-year-old?" The trainer went to an auction in Ocala, Fla., where he bought a $175,000 son of the stallion Montbrook.

With his first racehorse, Mady was about to get a fast education about the vagaries of the racing game. Thunderello made his racing debut at Saratoga in July 2001, finishing second to the most talked-about 2-year-old at the track. After Thunderello won his next start by 14 lengths in exceptionally fast time, a would-be buyer offered Mady $2 million for the colt. Considering that Thunderello was bred to be a sprinter and had almost no chance of developing into a Kentucky Derby candidate, this extravagant offer was one a rational owner couldn't refuse. Lake told Mady: "You make the call." And Mady decided: "I'm a little too attached to him. I'm going to hang on."

One week later, Thunderello was injured and sidelined for a year.

The colt suffered a slight tear in a suspensory ligament just as he was getting ready for a stakes race at Belmont Park. He resumed training in the spring but reinjured the same area and was knocked out of action again. Of his $2 million decision, Mady said, "I tried not to regret it. But after nine or ten months, I started thinking that I should have done the prudent thing."

Thunderello finally recovered from his physical problems, and this fall he has fulfilled his early promise. After narrowly losing his first start as a 3-year-old, he won an allowance race at Belmont by four lengths, and then captured a stakes at Philadelphia Park in impressive fashion. With the Breeders' Cup Sprint three weeks away, Lake pondered what to do.

He finally decided to send his lightly raced colt to Arlington Park to go up against tough, seasoned speeders such as Orientate and Xtra Heat. Second-guessers thought this was a rash move by a claiming-horse trainer out of his element in the big leagues. Even Lake conceded, "We knew it wasn't the right thing to do, management-wise. But we knew he has as much ability as any horse in the country." To disbelieving handicappers, he declared before the Breeders' Cup: "He will make the lead -- and do it easily."

Bettors ignored Thunderello, sending him to the post at odds of 48 to 1. But the colt came out of the gate like a rocket, outrunning Xtra Heat and all the others, zipping the first half mile in 43.91 seconds. He was ahead by a length when he turned into the stretch, before the favorite Orientate wore him down in the final yards and prevailed by half a length.

Since Orientate has been retired to stud, Thunderello has an excellent chance to establish himself as the nation's top sprinter. He will get a serious test in the De Francis Dash against California invaders Avanzado and D'Wildcat. After this race, Lake will prepare the colt for a trip to the $2 million Golden Shaheen Stakes in Dubai, the world's richest six-furlong race. He'll have the chance to validate further the judgment of his owner and trainer: Mady didn't make a seven-digit mistake by keeping him, and Lake is quite capable of playing in the big leagues.