In this web exclusive, Olympic downhill skier Lindsey Vonn discusses the reasons behind getting a knee replacement; what she discovered about herself upon retirement; the preparations necessary to re-enter competitive racing after several years away from the sport;

Silky Sullivan, ridden by Bill Shoemaker, wins the Santa Anita Derby by three lengths after trailing by 40 early in the race and by 20 entering the final turn. 1971 — Joe Frazier wins the world heavyweight title with a unanimous 15-round decision over Muhammad Ali at New York’s Madison Square Garden.