PHILADELPHIA — Philadelphia Phillies reliever Matt Strahm had just cracked open a can of Red Bull on Monday night, looked up from the bullpen, and on the first pitch of the game, there was a home run sailing over his head.

Four pitches later, there was another one flying deep into the night, traveling 420 feet, clearing the bullpen and clanking off the right-field seats.

Five pitches. Two home runs by Kyle Schwarber and Bryce Harper. Instant bedlam.

"I don’t think I’ve heard this place any louder," said Strahm, who confirmed with team officials that the noise level reached an ear-piercing 111 decibels. "I was talking to Hoffy (reliever Jeff Hoffman), and I couldn’t even hear myself talking. This place is unbelievable.

"You can’t explain what it feels like."

FOLLOW THE MONEY: MLB player salaries and payrolls for every major league team

Schwarber and Harper instantly turned Citizens Bank Park into a house party, hitting two home runs in the first inning of a postseason game for the first time in franchise history. And then Nick Castellanos added another one in the second inning.

The home run barrage, and ace Zack Wheeler’s dominant performance, provided the Phillies a powerful 5-3 victory in Game 1 over the Arizona Diamondbacks in the National League Championship Series, the D-backs’ first loss of the postseason.

"That gave us the momentum," said Castellanos, who has homered five times in his last three postseason games, tying Hall of Fame slugger Reggie Jackson’s record. "That unlocked the stadium. It unlocked the atmosphere. It just kind of put the night in our favor."

Uh, yes, to say the least.

The power show gave the Phillies 16 home runs this postseason, out-homering the opposition by 12 in their seven games. Their 12 homers alone in the past three games are the most by any team in a three-game span in postseason history. Since the last postseason, the Phillies have out-homered their opponents, 32-9, at Citizens Bank Park.

"I am amazed," Castellanos says. 'Not surprised."

The difference?

"When you’re watching something amazing like all of these home runs we’re hitting," he said, "you can appreciate it. But I’m not surprised because I know we’re capable of doing it."

The Diamondbacks, who didn’t trail for a single pitch in their three-game sweep against the Los Angeles Dodgers, watched in horror as Zac Gallen gave up three home runs to the first seven batters he faced after yielding only three homers in his last eight starts.

"They just ambushed us," Diamondbacks manager Torey Lovullo said. "They came out ready to jump on his fastball."

If the three home runs traveling 1,202 feet weren’t impressive enough, the Phillies provided a little theater, too, courtesy of Harper, who celebrated his 31^st birthday with 45,396 of his closest friends at Citizens Bank Park.

Harper, who like Schwarber swung on the first pitch, danced around the bases when his ball sailed into the right-field seats, crossed home plate, flashed three fingers on his left hand and one on his right, and blew them out like they were candles.

"It's crazy, sometimes I just do stuff, and that felt right," Harper said. "So I thought I would step on home plate and do that."

The Phillies players watched in awe, with some like shortstop Trea Turner thinking he was putting up four fingers to illustrate that he’s hit four homers this postseason, until later discovering the truth.

"I mean, everyone went nuts," said Schwarber, whose first-pitch homer, 117-mph off his bat, was a postseason record fourth leadoff homer. "This guy, he is looking for the moment, and he wants it. He’s doing such an unbelievable job for us.

"When he is going up to the plate, you are just thinking that he is going to do something special every time.

"Can that be unfair to have an expectation on a player? Sure. But that’s what everyone is thinking when you’re in the dugout, 'Man, what’s this guy going to do next?'"

BASEBALL in 2028 OLYMPICS: Bryce Harper says it'd be 'a dream' to play in Los Angeles Games

Well, the truth is that the Phillies are now starting to have the same expectations of Castellanos, who has five home runs this postseason from the No. 7 spot in the batting order.

"Nick definitely brings some swag to the game," Phillies outfielder Brandon Marsh said. "He’s having fun out there, just playing a kid’s game.

"I got the best seat in the house on deck watching him. It’s truly special, seeing a guy, with the pitching caliber we’re going up against, and taking care of business.

"He’s just an unbelievable talent."

So, if Reggie Jackson is Mr. October, just what are we supposed to call Castellanos?

"I don’t know," Strahm says. "Nick is Nick. There’s only one of them. I think your best bet is probably to hold four fingers up against him right now.

"I mean, if you tried to pitch around him, he’d probably hit that too."

The Phillies, who celebrated their victory with a strobe light and fog machine, know that one game hardly makes a series. They still need to defeat the D-backs three more times to reach the World Series for the second consecutive year. But they’re starting to feel invincible at home, winning a record 10 consecutive postseason games at Citizens Bank Park against National League teams, and are 27-11 overall at their ballpark in October.

Harper reminded everyone before and after the game that no one is going to take the D-backs lightly, praising them for their scrappy play. Once the team briefly celebrated their win, Harper was quite mellow, sitting alone in front of his locker and looking at his cell phone. He finally got up, showered, and met the media.

"I’m just very thankful to play this game," said Harper, who also drove in a run in the third inning, and is hitting .409 with a .567 on-base percentage and .955 slugging percentage this postseason. "I'm very thankful to be able to be in that spot in that situation. It's fun. I mean, it's a lot of fun.

"I’m pumped man."

Harper walked out of the clubhouse at 11:26 p.m. local time to see his family, but long after he departed, his teammates still couldn’t stop talking about him.

One day, they'll tell all of their friends and family, that they played with a player who could go down as one of the greatest clutch performers in the history of the sport.

The bigger the stage, the brighter the lights, there is Harper.

This is a guy whose career 1.044 OPS in the postseason ranks third among all players with at least 150 plate appearances, trailing only Babe Ruth and Lou Gehrig.

"It's really cool to see a player like that really exceed in these stages," saidSchwarber, "and show everyone what he's all about."

Once again.