Louisville, Ky. ? Jockey Mike Smith and trainer John Shirreffs kept saying Giacomo was a good horse. No one would listen.

Turns out the colt with the musical connection was a surprising hit at the Kentucky Derby.

Named for the 9-year-old son of singer Sting, Giacomo pulled the second-biggest upset in Derby history Saturday, winning at 50-1 odds. Giacomo finished a half-length ahead of Closing Argument, an even longer shot at 72-1.

After 12 tries, Smith finally got into the Derby winner’s circle, carried by the son of Holy Bull, one of his previous Derby losers.

“I’m so numb,” he said. “When I stood up at the wire, all the strength left my body, and I was hanging on for dear life.”

The victory was a sweet score for owners Jerry and Ann Moss of Los Angeles. He founded A&M Records with trumpeter Herb Alpert of Tijuana Brass fame. The ’70s pop duo the Carpenters was one of the former label’s biggest acts.

“It was hit records that got me here,” Moss said, “but this is a pretty great thing.”

Sting is a friend of the couple, who owned Giacomo’s mother, Set Them Free — the name of a hit song for the British rock star. They named another of their horses Styler, the last name of Sting’s wife, Trudie.

The colt came into the Derby with one victory in seven career races, including an 0-for-3 mark this year. He was fourth in the Santa Anita Derby, losing his final prep by two lengths.