Stewart's final major league win came on September 7th against the Yankees in relief during the 6th and 7th innings. The Nats were losing 4-2 when Stewart came in to face the number 6 batter, Gil McDougald, at the start of the bottom of the 6th inning at Clark Griffith stadium in Washington, D.C. A throwing error by the shortstop allowed McDougald to reach 1B on a grounder, but a line drive by Billy Martin to first baseman Pete Runnels resulted in an unassisted Double Play. The inning was closed by an Andy Carey flyball out to rightfield.
The Nats came out of the Top of the 7th inning scoring two Runs to tie the game on a Clint Courtney single to rightfielder Hank Bauer, which brought in runners Pete Runnels and Roy Sievers. In the Bottom of the 7th inning Stewart faced Joe Collins, Hank Bauer, Enos Slaughter, Mickey Mantle, Yogi Berra, and Bill Skowron. He allowed Hank Bauer to score on a single by Yogi Berra to right field.
Stewart was able to secure the victory in the Top of the 8th inning when the Nationals scored 2 Runs to gain the lead. Whitey Herzog brought in the winning run against Don Larsen on a fielder's choice. Bunky Stewart was replaced in the Bottom of the 8th after two innings of work. His actual final major league game pitching would come 8 days later in Kansas City.