It will go down in betting lore as the $9 million disqualification.
Kentucky Derby favorite Maximum Security crossed the finish line first but was subsequently disqualified Saturday, making long shot Country House the winner. It cost bettors who backed Maximum Security to win, place or show approximately $9 million, according to betting statistics provided by online horse racing site TwinSpires.com.
Maximum Security closed at 9-2 and appeared to hold off the field on a rain-soaked, sloppy track at Churchill Downs in Louisville, Kentucky. An objection was filed accusing Maximum Security of interfering with other horses, and race officials reversed the decision, giving Country House the victory.
Country House, at 65-1, had the second-longest odds of any Kentucky Derby winner.
Across the nation, there was more than $6.2 million bet on Maximum Security to win and only $520,907 on Country House. The largest win bet reported by TwinSpires on Maximum Security was $8,000, which would have paid a net $36,000. The largest win bet on Country House, per TwinSpires, was $2,500. It paid a net $162,500.
Maximum Security also had $1,495,408 bet to place and $1,272,082 to show.
At the SuperBook at Westgate Las Vegas, the reversal caused a mid-five-figure swing against the house in its Kentucky Derby futures odds market, which is separate from the national pari-mutuel pool.
"[We] went from a good-sized win to a good-sized loss," SuperBook sportsbook director John Murray told ESPN in a text message. "The SuperBook animal racing trade team is annoyed by the decision."
Only 1 percent of bets and 1 percent of the total amount wagered on the Kentucky Derby futures market at William Hill sportsbooks in Nevada were on Country House. Country House's odds were as long as 80-1 in February at William Hill.