LEXINGTON, Ky. — Skip Away, the third-richest North American racehorse in history, died from a heart attack Friday at the central Kentucky farm where he stood as a stallion.

Rick Trontz, owner of Hopewell Farm near Midway, Ky., said Skip Away had been diagnosed with a heart murmur, but the condition proved more serious than initially believed.

"The horse never showed signs of being lethargic or losing weight or losing interest in the breeding shed," Trontz said of the 17-year-old horse. "He just went real quick."

Skip Away was a three-time Eclipse Award winner, including Horse of the Year in 1998, champion 3-year-old male in 1996 and champion older horse in 1997-98.

He won 18 of 38 starts, earning $9.6 million. That was second to just Cigar all-time when he retired, but both horses have since been passed by Curlin.

One of Skip Away's career highlights was defeating Cigar in the first of two victories in the Jockey Club Gold Cup. He also won the Grade 1 Blue Grass Stakes, Woodbine Million and Buick Haskell Invitational as a 3-year-old, as well as the Breeders' Cup Classic and Hollywood Gold Cup later in his career.

Skip Away's stud fee had declined as a stallion in recent years, but Trontz said he did have some success — although none of his progeny matched his own success on the racetrack. Hopewell's website says he produced 48 stakes winners accounting for more than $17 million in earnings.

At the farm, where he had lived for a decade, he carried himself as a star.

"He knew he was the king," Trontz said. "He was always a little full of himself — playful, but not mean. He was real easy to be around."

Trontz said the horse would be buried in his familiar paddock.