PHOENIX -- After dropping two close contests to the D-backs that evened the National League Championship Series at two games apiece, the Phillies knew they needed to find a way to respond early in Game 5.

They had to shift the momentum back on their side, which, for the Phillies, usually means delivering a couple of towering homers.

But in the 6-1 win over the D-backs in Game 5 of the NLCS on Saturday at Chase Field, the Phillies pounced early by calling for a double steal in the first inning that resulted in Bryce Harper swiping home. It was the first steal of home in the Phils' 131-game postseason history. At 31 years old, Harper also became the oldest player to accomplish the feat in a postseason game since Jackie Robinson’s iconic dash home in the 1955 World Series at age 36.

“From the start of the playoffs, sort of the message to everybody was, ‘Let’s put pressure on people,’” said Phillies manager Rob Thomson. “Forcing them to maybe make some mistakes.”

As the Phillies went through their scouting report ahead of Game 5, first-base and baserunning coach Paco Figueroa identified an opportunity to be aggressive against the D-backs early in games.

When Zac Gallen pitches out of the stretch, the right-hander usually leans on a slide-step delivery in order to hold runners at first base more effectively. That move, paired with Gabriel Moreno’s stellar arm behind the dish, makes it nearly impossible for opposing teams to steal. The Gallen-and-Moreno battery allowed just one stolen base in four attempts during the regular season.

Most teams would shy away from challenging Gallen and Moreno on the bases. For the Phillies, it was the perfect combination.

With two outs in the inning and Harper on third, the Phillies felt confident Moreno would try to throw out Bryson Stott, who was at first, if he broke for second. Most catchers would pump fake in that situation to keep the lead runner at third and not concede a run. But with the type of arm Moreno possesses, the Phillies knew he would attempt to end the inning if Stott ran.

That’s when Thomson called for one of the gutsiest moves of this Phillies postseason run. Figueroa went to Stott and told him to take off for second. Third-base coach Dusty Wathan relayed the message to Harper.

“Just like Dusty said, he told me, ‘Hey, be aggressive right here,'” Harper said. “We’re going to be aggressive in this spot. Knowing how good Zack [Wheeler] is on the bump and trying to take advantage of that moment.”

Stott said the Phillies have worked on the play all season long. He recalls a similar play against the Mets last season that didn’t work out. But on Saturday, the play developed just as they expected.

As the Phillies second baseman took off for second, Moreno popped up from his crouch and fired a low throw to second baseman Ketel Marte. Once Moreno fired to second, Stott pulled up to avoid a tag or get into a rundown. Harper, meanwhile, sprinted for home as soon as the ball was released. He knew third baseman Evan Longoria was too far from the bag for him to get picked off at third.

Marte received the throw from Moreno and fired back home, but the catcher was unable to corral the short hop, resulting in a collision between him and Harper. Moreno stayed in after being checked on by a team trainer and finished the game.

“We work on that a lot,” said D-backs manager Torey Lovullo. “I think if we just play pitch and catch and he drives the throw into home plate and gives Gabi a chance to catch that ball and lay the tag down on Harper, he is out by eight, 10 feet. You're trying to collect an out right there and get off the field right there, down 1-0. He just short-hopped the catcher, and that type of stuff happens from time to time.”

Harper, on the other hand, scored a much-needed second run of the frame, giving Wheeler some early run support.

“It was a big run for us in that inning,” Figueroa said. “We do that throughout the season and early in the game, but normally, teams don’t throw through late in the game. In that situation, they for sure trust that guy that is behind the plate, he just didn’t execute the throw. It was a risk that we were willing to take.”

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In order for it to work, everything needed to go according to plan. Harper needed to break at the perfect time. Stott needed to pull up precisely when he did. Any slight hesitation from either player and the Phillies could’ve lost momentum by ending an inning with a baserunner getting thrown out at the plate.

Harper later blasted another postseason home run to pad the Phillies’ lead in the sixth, and in doing so, he joined the Rays' Randy Arozarena as the only players to steal home and hit a homer in the same postseason game.

“I just want to win,” Harper said. “Whatever that takes, whatever that’s going to be, whatever that’s going to look like. That was a big game for us.”