Jim "Mattress Mack" McIngvale, a business magnate from Houston, Texas, raised his original Kentucky Derby bet on Essential Quality(horse name) from $500,000 to $2.4m by the time the colt reached the starting gate, so he could have won $6m.
He wouldn't get any of it back.
Essential Quality, the 5-2 favorite, finished fourth in the 147th Run for the Roses, leaving McIngvale with another major defeat as legendary trainer Bob Baffert won the Derby for the seventh time with Medina Spirit.
Mattress Mack previously bet $1 million on the Houston Cougars to win the NCAA tournament at 9-1 odds. His alma mater was unable to beat the eventual champion Baylor Bears in the Final Four.
McIngvale's most recent major victory was after Super Bowl 55, when he converted a $3.46 million gamble on the Tampa Bay Buccaneers into a $2.75 million benefit. The mattress salesman usually transforms his bets into shop deals, which will compensate any loses.