On October 3, 1951, Lockman scored the tying run, just ahead of Bobby Thomson, on Thomson's home run that gave the New York Giants the National League championship—baseball's "Shot Heard 'Round the World." Lockman's one-out double against the Brooklyn Dodgers had scored Alvin Dark with the Giants' first run of the inning, and made the score 4–2, Brooklyn. His hit knocked Dodger pitcher Don Newcombe out of the game, and, on the play, Giant baserunner Don Mueller broke his ankle sliding into third base. While Mueller was being carried off the field to be replaced by pinch runner Clint Hartung, Dodger manager Chuck Dressen, acting on the instructions of Dodger bullpen coach Clyde Sukeforth, called on relief pitcher Ralph Branca, whose second pitch was hit by Thomson over the head of Andy Pafko into the Polo Grounds' lower left field stands for a game-winning, three-run homer. However in the 1951 World Series, won in six games by the New York Yankees, Lockman hit .240 with a home run. Three years later, he batted only .111 in the 1954 Fall Classic, but the Giants swept the Cleveland Indians to win the world championship.