ST. LOUIS -- Before the music blared, the champagne sprayed and the players rejoiced, the Cardinals’ players and coaching staff huddled in the clubhouse on Sunday afternoon. Manager Mike Shildt asked anyone who hadn’t been to the playoffs before to raise their hand, and the majority of the players did.

Most of them had arrived during the three years that the Cardinals missed out on October. But with Sunday’s 9-0 rout of the Cubs at Busch Stadium, the Cardinals clinched their first National League Central title since 2015, setting up an NL Division Series showdown with the Braves, beginning Thursday in Atlanta.

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“Back in ‘15, most of our roster had been [to the postseason] before because we had been there year after year after year,” Cardinals general manager Mike Girsch said. “To finally get back in -- hopefully we just started another stretch.”

Young players who have never played postseason baseball and veteran players who have a history in October helped the Cardinals to this year’s division title. After losing four straight games this week, the Cardinals needed a win or a Brewers loss on Sunday to avoid an NL Central tiebreaker. So they turned to their young ace to start and their veteran hitters to produce.

Jack Flaherty threw seven dominant innings on 69 pitches, allowing two hits and striking out six. He was sent to the on-deck circle in the bottom of the seventh before being pulled for pinch-hitter Randy Arozarena, and the 47,212 fans at Busch Stadium gave him a standing ovation. Then Adam Wainwright went to the top step of the dugout to pump up the crowd, and Flaherty received a curtain call.

“I was not ready for that,” Flaherty said. “I knew I was done, but Shildt sent me out and called me back. It was not something I expected. I was not going to go back out, but they didn’t really give me a choice. That was something else.”

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“He deserved that,” Wainwright added. “We’re not celebrating right now if Jack doesn’t do what he did in the second half.”

Flaherty was pegged to close out the division after his historic second half. Including Sunday, the 23-year-old has a 0.91 ERA since the All-Star break, third best in MLB history. He’s pitched Game 162 in each of the last three years, taking a loss in the 2017 and ‘18 finales. He wasn’t going to let it happen again with so much at stake.

“Way different,” Flaherty said. “When you’ve got something to play for, when you play with these guys, it just means something different. … Situation was what it was, so it was about going out and doing what we could. You treat every game like it’s the biggest game of the year, when it comes down to it being the biggest game of the year, it all stays the same.”

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After Flaherty set the tone with an eight-pitch top of the first, the Cardinals’ offense got out to a fast start with two runs in the bottom of the inning. The bats added seven more runs by the end of the fourth inning, including home runs from Dexter Fowler, Matt Carpenter and Paul Goldschmidt, all of whom have been to the postseason.

“It’s indescribable,” Carpenter said. “This is what it’s all about. This is why you do it every day. This is the whole purpose of the whole thing, so to get here and make it happen, it’s a lot of fun."

The Cardinals believed throughout the year they would end up at this spot. Despite all the ups and downs -- remember May, when they went 9-18? -- many of them thought that the rotation would come together and the lineup would click.

“There was just a hunger to what we were doing, and that pretty much sums up this team,” Shildt said. “It’s a hungry group, it’s only getting hungrier.”

Now the Cardinals move on to Atlanta, where they open the NLDS against the NL East champion Braves on Thursday at SunTrust Park. They don’t want Sunday to be the last time they are doused in champagne this year.

“It’s a taste -- I’m telling these young guys -- it’s a taste of what you’ll chase for your whole career,” Wainwright said. “Once you taste that champagne in your beard or feel that burn of cold beer going down your back, there’s nothing like it. The top of your head going numb. You can’t replicate that in any other situation.”