Sabathia threw his first career complete game in the playoffs and set a postseason career high with nine strikeouts.
Sabathia's 121 pitches set a postseason career high, and his 15 swinging strikes matched his most since Game 1 of the 2009 ALCS against the Angels.
Sabathia won two games in a postseason series for the first time since the 2009 ALCS against the Angels.
The Yankees improved to 93-0 at home in the postseason when leading after eight innings.
Before Game 5, New York's last win in a winner-take-all contest was Game 7 of the 2003 ALCS, when Aaron Boone hit a walk-off homer in the 11th inning to defeat the Red Sox.
Baltimore fell to 1-4 in winner-take-all games.
Mark Teixeira's fifth-inning steal was the first of his postseason career.
Curtis Granderson's seventh-inning home run off O's reliever Troy Patton ended the O's left-hander's string of 18 consecutive innings without allowing an earned run, dating back to July 2.
Granderson, who entered the game 1-for-16 in the series with nine strikeouts, went 2-for-3 and hit his sixth career postseason homer.
The Yankees had three hits in the fifth inning after recording one in their previous nine.
Nate McLouth led all AL players in the ALDS with five RBIs and tied with Derek Jeter for the most hits with eight.
Baltimore's Adam Jones (2-for-26), Matt Wieters (3-for-24), and Mark Reynolds (3-for-22) combined to hit .111 with two RBIs and 21 strikeouts in the postseason.
New York's Alex Rodriguez (2-for-16), Nick Swisher (2-for-18), Robinson Cano (2-for-22), and Russell Martin (3-for-17) combined to hit .123 in the series.
Rodriguez was benched in Game 5, in favor of Eric Chavez, for the first time in his Yankees postseason career. He had started all of his 57 career playoff games as a member of the Yankees heading into Game 5.