Chicago Cubs pitcher Greg Maddux slides on a wet infield tarp during a rain delay in the first night game at Wrigley Field on Aug. 8, 1988. The Hall of Famer and eight-time All-Star who won four consecutive NL Cy Young Awards (1992-95), nicknamed “Mad Dog” and “The Professor,” turned 50 years old on April 14, 2016. (Heinz Kluetmeier)

GALLERY: SI’s Best Photos of Greg Maddux