Despite their history as the National League's most successful franchise—the second-most World Series titles in baseball behind the New York Yankees— this was the Cardinals first postseason appearance since the league went to divisional play. Their last postseason trip had been to the 1968 World Series when they lost to the Detroit Tigers—the last year before divisional play. The Atlanta Braves were making their first postseason appearance since 1969, the first year of divisional play. The Cardinals were led by Gold Glove first baseman and solid hitter Keith Hernandez, while the Braves were led by Dale Murphy, who was later named the season's MVP. The Cardinals had been the first team to clinch a playoff berth on September 27 while the Braves were the last to make the playoffs, clinching the West on October 3 when the Giants beat the Dodgers.

On a side note, Atlanta's manager Joe Torre and two of his coaches Bob Gibson and Dal Maxvill were known for playing for the opposing St. Louis Cardinal team while Cardinal coach Red Schoendienst previously played for the Braves and Cardinal coach Hub Kittle previously managed in the Braves organization.

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Wikipedia