Past winners of the Triple Crown

Here are the past winners of the Triple Crown.

In 2015, American Pharoah became the 12th horse, and the first since Affirmed in 1978, to win the Triple Crown.

Nyquist, the winner of last year's Kentucky Derby and the betting favorite in the Preakness Stakes, failed to accomplish the feat. Nyquist finished third in the Preakness Stakes and was pulled out of the Belmont Stakes due to an illness.

Check out the past Triple Crown winners below:

2015 - American Pharoah

1978 - Affirmed

1977 - Seattle Slew

1973 - Secretariat

1948 - Citation

1946 - Assault

1943 - Count Fleet

1941 - Whirlaway

1937 - War Admiral

1935 - Omaha

1930 - Gallant Fox

1919 - Sir Barton