The Triple Crown is the pinnacle of Thoroughbred racing, a rare feat that has only been achieved 11 times.
After winning both the Kentucky Derby and the Preakness, American Pharoah has a chance to become the first Triple Crown winner since 1978 if the horse can win the Belmont Stakes in June.
There have been many Triple Crown near-misses over the years, including in two of the last three years. In 2012, I'll Have Another won the Kentucky Derby and the Preakness before being scratched the day before the Belmont Stakes due to tendonitis.
Last year, California Chrome won the Crown's first two races and was the morning favorite at Belmont. However, the horse bumped with another horse out of the gate and wound up finishing in fourth place.
Here is the full Triple Crown winner history:
1919 Sir Barton
1930 Gallant Fox
1937 War Admiral
1943 Count Fleet
1977 Seattle Slew