January 1, 1965
Seven-time MLB All-Star Sandy Koufax was unstoppable -- until he jammed his pitching arm while diving into second base during a 1964 game. Shortly after he could not straighten his arm, and was diagnosed with traumatic arthritis. He retired two years later. During his 11-year career Koufax took home four World Series championships, three Cy Young Awards, two World Series MVP awards, two Babe Ruth awards and three Triple Crowns. He also pitched four no-hitters and a perfect game.