MLB players will wear number 42 today on the 78th anniversary of Jackie Robinson's first game with the Brooklyn Dodgers. This August 1949 issue of SPORT Magazine marks his first of several appearances on the cover while an active player.

Because Sports Illustrated didn't find its footing covering pro sports until after Robinson retired, Jackie's S.I. cover debut came a quarter century after his death, and is less sought-after than his early TIME and SPORT issues.