The 1971 Major League Baseball postseason ran from October 2 to October 17, 1971, featuring the Baltimore Orioles, Oakland Athletics, Pittsburgh Pirates, and San Francisco Giants. Notably, the Oakland Athletics ended a 40-year postseason drought (their first since 1931, when they were in Philadelphia), beginning a run of five straight playoff appearances, while the San Francisco Giants made their first trip since 1962—marking the first time both Bay Area teams reached the postseason. In the American League Championship Series, the Orioles swept the Athletics, powered by complete games from Mike Cuellar and Jim Palmer, to secure their third consecutive pennant. The National League Championship Series saw the Pirates defeat the Giants 3–1, highlighted by Bob Robertson becoming the first player to hit three home runs in a single postseason game. The Pirates then captured their first World Series title since 1960 by defeating the Orioles in a thrilling seven-game series, clinching their fourth championship in franchise history. This postseason is remembered for ending the longest active playoff drought in major North American sports and for launching the Athletics' dominant early-1970s dynasty.