With the Giants only needing four starters for the playoffs, Lincecum was used as a relief pitcher in the postseason. In Game 2 of the NLDS against the Cincinnati Reds, Lincecum threw two shutout innings, though the Giants would lose 9–0. He picked up the win in Game 4 of the NLDS, throwing 4 1/3 innings of relief and allowing just one run as the Giants won 8–3 to force a deciding Game 5, which they would also win. After Lincecum pitched two hitless innings in Game 1 of the NLCS against the Cardinals, Bochy decided to give him the start in Game 4. Lincecum gave up four runs in innings, taking the loss in San Francisco's 8–3 defeat. That loss put the Giants down three games to one in the series, but they won the next three games, advancing to the World Series for the second time in three years. In Game 1 of the World Series, Lincecum relieved Barry Zito with two outs in the sixth inning, getting the last out and throwing two further scoreless innings as the Giants defeated the Detroit Tigers by a score of 8–3. Lincecum relieved Ryan Vogelsong with two outs in the sixth inning of Game 3, again throwing scoreless innings, this time in a 2–0 victory. The Giants swept the Series for their second title in three seasons.