High Quality Content by WIKIPEDIA articles! The 2012 National League Championship Series was a best-of-seven playoff pitting the San Francisco Giants against the St. Louis Cardinals for the National League pennant and the right to play in the 2012 World Series. The series, the 43rd in league history, began Sunday, October 14, and ended Monday, October 22, with Fox airing all games in the United States. The Giants came back from 3–1 deficit and outscored the Cardinals 20–1 over the final three games to win the series 4–3.