LOUISVILLE, Ky. — The Breeders' Cup Challenge "win and you're in'' series of races had been around for a decade. There were approximately 500 Challenge races. None of those races had been won by a horse based at Parx Racing.

Then, in the space of a few hours on Sept. 29 at Belmont Park, Imperial Hint, stabled in Barn 4 at Parx, and Discreet Lover, stabled in Barn 23, won the Vosburgh Stakes and Jockey Club Gold Cup, respectively — "win and you're in'' races for Saturday's BC Sprint and BC Classic at Churchill Downs.

Eight days later, Jaywalk, stabled in Barn 8 at Parx, made the same trip to Long Island and took down the Frizette, another "win and you're in'' race. The 2-year-old filly will run in Friday's BC Juvenile Fillies.

So, in barely a week, three Parx horses won Grade I races that got their owners an all-expenses-paid trip to the two-day BC extravaganza with its 14  races and $28 million in purses.

The wonderful sprinter Imperial Hint was no surprise. He was 1-5 in the Vosburgh. He finished second in last year's Sprint and should be the favorite this time. Termed the "little rocket ship'' by Belmont Park and Breeders' Cup announcer Larry Collmus, Imperial Hint has won seven of his last eight 6-furlong races, the distance of the Sprint. The lone defeat was by just 1 length last year at Del Mar, where the winner ended up on the best part of the track in the stretch.

Trainer Luis Carvajal has a small stable. Imperial Hint owner Raymond Mamone, 86, has owned horses for 42 years but never had anything close to Imperial Hint, America's fastest horse in 2018, one more win from being named champion Sprinter.

Imperial Hint is continuing a great tradition of sprinters at the track that was originally called Keystone. Gallant Bob, a winner of 23 races, and My Juliet, a winner of 24 races at 16 tracks, both won Eclipse Awards as champion sprinter in the mid-1970s.

If Imperial Hint was obvious that day in New York, Discreet Lover was not. In fact, nothing about Discreet Lover has ever been obvious.

Owner-trainer Uriah St. Lewis, a native of Trinidad, bought Discreet Lover for $10,000. He ran the horse in the 2016 Ohio Derby and Discreet Lover went off at 87-1. He finished third. Discreet Lover was 238-1 in that year's Pennsylvania Derby. He beat just two horses.

But St. Lewis never stopped believing in his horse, and over time Discreet Lover got almost imperceptibly faster. It never bothered St. Lewis that his horse went off at 72-1, then 86-1 and 84-1. The horse would run third or fourth sometimes in major races and when Discreet Lover came out of the starting gate in the Jockey Club Gold Cup in his 44th career race, the horse was just shy of $1 million in earnings. Oh, and he was 45-1.

Discreet Lover is an old-school horse with very little early speed. It was clear if he ever got a contested pace in front of him, he could take down one of the big races. Well, he finally got his pace and there he was, relentlessly charging at the leaders and getting to the front just before the wire.

"It was one of those feelings you will never forget,'' St. Lewis said.

St. Lewis loved horses from a young age and then when his family moved to New York, he found himself at Aqueduct every day making some bets. Then, he got a job fixing computers for a company that made the betting machines.

St. Lewis said his wife told him, "You keep betting horses and losing your money, you don't know nothing about it.''

She dared him to learn more about the game. They sold everything and went to Oklahoma, where he learned about training.

He came back and settled in at Parx, where he definitely was not an overnight success. He won a few races at the start, but then winning became very difficult. The stable won just 23 of 824 races from 2006 to 2014. Then, Discreet Lover arrived and St, Lewis kept swinging for the fences

"You could be the hero or the goat,'' St. Lewis said. "Right now, I'm the hero. I was a goat for a long time.''

Jaywalk's connections are no strangers to big races. Trainer John Servis has won the Kentucky Derby and Preakness with Smarty Jones and the Kentucky Oaks with Cathryn Sophia. Majority owner Chuck Zacney won that Kentucky Oaks with Servis and also won the Preakness and Belmont Stakes with Afleet Alex. Leonard Green is partners with Zacney on Jaywalk.

Zacney, who loves to watch his horses run, will be watching this one on television. He flew over for the Eagles game last Sunday in London, is spending a few days on vacation in Ireland and is due to land in Philadelphia about two hours before Jaywalk's race, scheduled for 4:40 p.m. Friday.

"She was one of those horses when she walked out of the barn at the sale, she jumped right out at you,'' Servis said.

Always Sunshine, also based at Parx with trainer Ned Allard, will be in against Imperial Hint in the Sprint. He will be a long shot but has a chance to hit the board.

Imperial Hint should win. Jaywalk could win. Discreet Lover probably won't win, but that $10,000 has turned into $1,374,685, so the horse and the St. Lewis family have already won.