First Samurai is a thoroughbred race horse born February 2, 2003. He was a contender for the Triple Crown in 2006, but after a starting gate incident contributed to his defeat in the Toyota Blue Grass Stakes he was ruled unlikely to race in the Kentucky Derby. Two weeks after the race, First Samurai was diagnosed with two broken ribs following an ultrasound. He was not entered in the Kentucky Derby, with his injury cited as the reason. The Blue Grass ultimately proved to be his final race.