WASHINGTON — Alex Bregman held his bat in the air with his left hand and walked five paces down the first-base line, his head turned to watch the final landing spot of a baseball he had launched toward Capitol Hill.

The ball fell into the stands for a seventh-inning grand slam that erased any doubt the Houston Astros would beat the Washington Nationals, 8-1, in Game 4 of the World Series on Saturday night. Just as important, perhaps, the blast gave Bregman, Houston’s cleanup hitter, some of his missing swagger back.

The night before, in Game 3, the Nationals chose to walk Michael Brantley ahead of Bregman in the sixth inning. That loaded the bases with two outs, and Bregman grounded out. In the Astros’ dugout at the time, Carlos Correa shook his head, knowing that this insult to a proud hitter would most likely come back to haunt the Nationals.

Correa said he knew Bregman would be angry about the tactical move, and he predicted after Game 3 that Bregman would make Washington pay for it. Twenty-four hours later, Bregman did just that, turning a three-run game into a blowout that evened the best-of-seven series at two games apiece.