The 1972 National League Championship Series was played between the Cincinnati Reds and the Pittsburgh Pirates from October 7 to 11. It was the fourth NLCS. Cincinnati won the series three games to two to advance to the World Series against the Oakland Athletics. The Reds became the first team in major league history to advance to the World Series without the best record in their respective league, made possible by the Junior and Senior Circuits each splitting into two divisions in 1969. In the previous three post seasons, the team with the best record in each league advanced to the World Series.