ATLANTA -- Nick Castellanos looked skyward on his back in the right-field grass with his arms stretched overhead for a few moments after robbing William Contreras of a hit for the second out of the ninth inning.

The Braves had cut the Phillies’ lead to one run with a three-run homer by Matt Olson just one batter earlier in the bottom of the ninth, and Castellanos’ catch put a major damper on their rally. As he took a moment to himself in the outfield, was he happy? Was he relieved?

“All of the above,” Castellanos said.

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Phillies fans have been waiting a long time for Castellanos’ big moment. But nobody has been waiting longer than the right fielder, who the Phils signed to a five-year, $100 million deal on March 22.

After putting up his lowest full-season batting average (.263) and slugging percentage (.389) since 2015, Castellanos had arguably the biggest moment of his tenure with Philadelphia on Tuesday afternoon, going 3-for-5 with three RBIs and a run scored as the Phillies defeated the Braves, 7-6, in Game 1 of the National League Division Series.

Castellanos became the first Phillie to have three hits in the first four innings of a postseason game since right-hander Brett Myers in Game 2 of the 2008 NL Championship Series. In 136 regular-season games this year, Castellanos never had a three-hit, three-RBI game.

Castellanos' rally-killing catch in the ninth required him to cover 64 feet in 4.1 seconds, allowing him to convert a 55% catch probability for a three-star play. During the regular season, Castellanos converted just three of 13 three-star chances (51-75% catch probability) and had -11 outs above average, tied for the fourth worst among MLB outfielders.

So what’s changed from the regular season to now? While the high stakes and bright lights of the postseason can get to some players, Castellanos finds it the perfect environment to slow everything down.

“It's kind of just a fresh start, a clean slate, so to speak,” Castellanos said. “And obviously these games are really intense. For me, that helps me lock in and kind of slow things down. It's just a lot of fun. Baseball is really, really fun right now.”

Castellanos entered Tuesday 4-for-27 with one RBI in seven career postseason games. He went hitless in the NL Wild Card Series against St. Louis this past weekend, but he drew a walk and scored during the Phillies’ ninth-inning rally in Game 1.

In Atlanta, Castellanos drove in Philadelphia’s first run of the game with a first-pitch two-out single in the first inning. With two outs in the fourth, the Braves intentionally walked lefty Bryce Harper to get to Castellanos with the bases loaded. Castellanos responded with a two-run RBI single off righty reliever Jesse Chavez.

“I thought he played great, from at-bat one to the ninth inning there,” Harper said. “I thought our whole lineup had a really good plan today against [Braves starter Max] Fried. Timely hitting with two outs also. Just really I think all around I thought everybody did a great job. And what a team win.”

“The beautiful thing about the postseason is that nothing in the regular season matters anymore,” said Zach Eflin, who was on the mound for Castellanos’ catch. “It really depends [on] how you showed up and prepared the whole season, and to go out and perform. He’s put in the work each and every single day. And it’s awesome to see it pay off today. He’s a bulldog up there with the bat, and he had himself an awesome day.”

Tuesday’s performance suggested a turnaround for Castellanos after the outfielder spent the majority of September on the injured list with a right oblique strain. Manager Rob Thomson was encouraged by the way Castellanos has been playing, and he hopes it’s “the start of something.”

“Today it felt great,” Castellanos said, “and that's the only thing really that I'm focused on. And then getting ready to go and make sure it feels great again tomorrow.”