Martin Whiteford "Mr. Shortstop" Marion was an American Major League Baseball shortstop and manager. Marion played for the St. Louis Cardinals and the St. Louis Browns between 1940 and 1953. He was a defensive stalwart of the Cardinals' dynasty in the 1940s, which saw them win three World Series in a five year span, and was named the National League Most Valuable Player in 1944, the first shortstop in the history of the National League to win the award. Marion managed the Cardinals in 1951, the Browns from June 10, 1952, through 1953, and the Chicago White Sox from September 14, 1954 through 1956. During his career, he batted and threw right-handed, stood 6 feet 2 inches (1.88 m) tall and weighed 170 pounds (77 kg).

The St. Louis Cardinals are an American professional baseball team based in St. Louis. The Cardinals compete in Major League Baseball (MLB) as a member club of the National League (NL) Central Division. Since the 2006 season, the Cardinals have played their home games at Busch Stadium in downtown St. Louis. One of the nation's oldest and most successful professional baseball clubs, the Cardinals have won 11 World Series championships, the most of any NL team and second in MLB only to the New York Yankees. The team has won 19 National League pennants, third-most of any team behind the Los Angeles Dodgers and San Francisco Giants. St. Louis has also won 15 division titles in the East and Central divisions.