It was ruled that Maximum Security stepped out of its lane and impeded the run of another horse.
Maximum Security couldn't secure his win at the Kentucky Derby.
Maximum Security led all the way in the Kentucky Derby on Saturday, only to become the first victor disqualified for interference in the race's 145-year history.
For the first time in the 145-year history of the Kentucky Derby, the first horse across the finish line was disqualified for a foul on the track.
The Associated Press reported that Omaha Beach, who just turned 3 in April, would undergo surgery in Kentucky last week.
Code of Honor was moved up to second and Tacitus was third.
"No words can describe this".
The objection was filed and stewards took about 20 minutes reviewing the race from several angles before declaring Country House the victor.
UK: Defence Secretary Gavin Williamson SACKED over National Security Council Leak
Mr Williamson blamed a vendetta by Sir Mark, who is also the Cabinet Secretary, for his sacking, The Times reports. "No other, credible version of events to explain this leak has been identified", she added.
"I really lost my momentum around the turn", Prat told NBC. The decision handed the victory to Country House, which started the race at 65-1, and a first-time win to hall of fame trainer Bill Mott.
"Looking at the toteboard there's probably a lot of people that didn't think we could win", Mott said, "but that's horse racing". "If what happened to us was the only thing they were looking at I don't think you would have seen a disqualification".
Flavien Prat, the jockey of Country House, filed a rider's objection claiming that Maximum Security veered out of his path in the final turn, and it was upheld following a lengthy review, ESPN reported. Some who had wagered on Country House to win immediately tossed away their tickets at the finish, only to then scramble on the floor of the stands at Churchill Downs, frantically searching for their betting slips. The Kentucky-bred horse is jointly owned by Maury Shields, Eugene "Guinness" McFadden and LNJ Foxwoods.
Instead, previously undefeated Maximum Security was dropped to 17th of 19 horses. In 1968, Dancer's Image failed a drug test and was disqualified long after the race ended. His other horse, Roadster, was 15th.
Everyone thought favorite Maximum Security won Saturday's Kentucky Derby. "It took quite long", Prat said about waiting for the review to be completed by Derby officials.
Country House will go for the second leg of the Triple Crown at the 144th Preakness Stakes on May 18 on NBC and the NBC Sports app.
Justify was trained by Bob Baffert, who also trained the previous Triple Crown victor, American Pharaoh, in 2015.