PHILADELPHIA -- Brandon Marsh hit a three-run homer and J.T. Realmuto lined an inside-the-park home run that sent the Philadelphia Phillies bolting headfirst into the National League Championship Series for the first time since 2010 with an 8-3 win over the Atlanta Braves in Game 4 Saturday.

Realmuto became the first catcher to hit an inside-the-parker in postseason history, and Bryce Harper punctuated the romp with a clinching home run that helped the Phillies take the National League Division Series 3-1 against the World Series champion Braves.

"We had ups and downs during the season, just like any other club does. But they knew that they were going to come out of it at some point and start winning again,'' Phillies manager Rob Thomson said. "And we did.''

The Phillies will face either the San Diego Padres or the Los Angeles Dodgers in the NLCS. The Padres held a 2-1 lead over the Dodgers going into Game 4 of the NLDS matchup Saturday night.

Atlanta's loss meant Major League Baseball hasn't had a repeat champ since the New York Yankees won three straight from 1998 to 2000.

"Like I told them, the goal when we leave spring training is to win the division. Until you win the division, you don't have a chance to do anything special because you never know what's going to happen, you don't know what team's going to get hot, what things have to go right for you to go deep into the postseason,'' Braves manager Brian Snitker said.

"And we got in. It didn't happen for us this year,'' he said.

Philadelphia finished third in the NL East, 14 games behind the 101-win Braves this season, but now is hitting on all cylinders under Thomson. He took over for the fired Joe Girardi and transformed a team that was 22-29 in early June.

"We just got off to a little bit of a slow start and kind of spiraled. And May was a really tough month. It was a really tough schedule,'' Thomson said.

"Then once we hit June, the schedule kind of lightened up a little bit and we started winning, and guys started getting confidence and believing that they could win and believing that, OK, now this is the team that we thought we were. And just kept going,'' he said.

And the Phillies used a dose of Marsh Madness to keep the party rolling in October.

Heck, call it Mash Madness, as the Phillies turned Citizens Bank Park into a cozy home bandbox for the second straight game -- and with another fired-up, towel-waving crowd along for every long ball.

After Rhys Hoskins spiked his bat on a three-run shot in a Game 3 win, it was Marsh's turn in the second inning to hammer his own three-run homer in Game 4.

Braves starter Charlie Morton was hit on his pitching elbow by Alec Bohm's single traveling 71.9 mph to lead off the inning. After being checked, Morton allowed a single to Jean Segura and hung a 2-2 curveball that the No. 9 hitter Marsh launched deep into the right-field seats for a 3-0 lead.

The 24-year-old Marsh is known as much for his stringy hair and ZZ Top-esque beard as he is for being one of the top young players on the Phillies. Marsh, who also doubled in the fourth, was acquired from the Los Angeles Angels in August just ahead of this season's trade deadline. Phillies president Dave Dombrowski swung another deadline deal with the Angels that got them Game 4 starter Noah Syndergaard, also known for his long locks.

Hey, it will be easy for the Phillies to let their hair down and party.

Reliever Brad Hand was one of six Philadelphia pitchers and got the win.

Syndergaard, bumped from the rotation at the end of the season, wasn't asked by Thomson to do much other than keep the Phillies in the game, and maybe go unscathed once around the order. Syndergaard delivered with three strikeouts in three innings in a brief throwback to his commanding Thor days with the New York Mets.

Orlando Arcia hit a solo shot off him in the third to make it 3-1.

Realmuto then hustled his way into postseason history.

He connected to lead off the third inning against reliever Collin McHugh. The ball hit the angled portion of the wall beyond the reach of center fielder Michael Harris II, and the carom rolled along the warning track toward right-center. Ronald Acuña Jr. stood in right field watching the play and didn't start running toward the ball until Realmuto was well past first base. Realmuto, who runs extremely well for a catcher, made a headfirst slide into the plate well ahead of the relay.

With that, it was bedlam inside the park, as a sellout crowd of 45,660 was deliriously cheering, every sense tingling that there wasn't going to be a Game 5.

Nope. Just Game 3 of the NLCS back in Philly on Friday.

Harper hit a solo homer in the eighth, the second of the series for the reigning NL MVP.

It seemed fitting the trio of Phillies sluggers that form the heart of the franchise put the game away in the sixth. Hoskins-Realmuto-Harper all had RBI singles that made it 7-2 and a series clinch a mere formality.

The Phillies trotted out 2008 World Series champion Pat Burrell to throw the first ceremonial pitch after his teammate from '08 Shane Victorino did the same before Game 3. The Phillies' run of five straight postseason appearances -- which included the 2009 NL pennant -- stretched from 2007 to 2011 until the franchise was saddled with so many dry years without hope. They no longer have to look at Burrell, Victorino and other members of that run as the only reminders of postseason stars -- Harper, Hoskins, Realmuto and Marsh have carved their own October marks, with at least one more series ahead.