“I don’t know if that was in their playbook, but it worked,” Bochy said.

The Nationals, who had the best record in the National League, were largely neutralized.

Their closer, Drew Storen, could not close out Game 2. And other than Bryce Harper, who drove in four of their nine runs in the series — two scored on an error — and Rendon, their best hitters disappeared. Leadoff hitter Denard Span hit .105 for the series, which was better than the No. 3 and No. 4 hitters — Jayson Werth batted .059, and Adam LaRoche hit .056. Ian Desmond, the No. 5 hitter, hit .167.

And then there was the fielding that betrayed them Tuesday night in front of a more energetic crowd.

“The game, the situation they were in, can make you a little nervous,” said Giants first baseman Brandon Belt, who hit the game-winning, 18th-inning home run in Game 2. “Sometimes it makes you play better and sometimes it gets to you.”

Just as the Giants received a gem from Tim Hudson, who had struggled down the stretch, they received another in the clincher from Ryan Vogelsong, who was winless in five September starts. But he no-hit the Nationals until the fifth inning and was flawless other than when he allowed a single to Desmond and a double to Harper — the only hits and runs he allowed in five and two-thirds innings.

The crowd chanted “Vogey” on his trip back to the dugout, aware that it could be the last time he does so for the Giants, the team that drafted him, traded him away, got him back and revived his career. An unlikely hero of their 2012 World Series team, Vogelsong is now 37 and an impending free agent who floundered down the stretch. But he was splendid in Game 4, his late-tailing fastball and sharp curveball keeping the Nationals in check.