Sports: Baseball & Basketball
Career Years: Baseball (2952, 1954-1963) Basketball (1939-1940, 1943-1944, 1952-1953, 1958-1964, 1966-1968)

In any professional sport, the two categories that are most often used to measure an athlete's greatness are All-Star appearances and championships won. Gene Conley is the only athlete in sports history to win a championship in two of the four major American sports. As a pitcher, he was named to four All-Star teams and won a World Series in 1957 with the Milwaukee Braves. As a forward with the Boston Celtics, Conley racked up three consecutive championships from 1959–1961. That's a total of four rings in two different leagues, fam. Charles Barkley, Dan Marino, and Bron Bron have to be hurting right now.