WHEN HARRISON BADER found out that his childhood dream was coming true, his first reaction was unexpected: disappointment.

St. Louis, where he’d spent the past five and a half seasons as a member of the Cardinals, had become home. The team drafted Bader out of Florida in 2015, and when he was called up in 2017, he became a fan favorite. As the Cardinals ownership and front office told him that he was part of their roster’s core and the team’s future, Bader planted roots in the community. He was named the King of St. Louis Mardi Gras. He befriended local politicians like Missouri state senator Brian Williams and was working with him to bring a PGA golf event to St. Louis.

But on Aug. 2 of this season, when his phone rang four minutes before the trade deadline with a call from Cardinals president of baseball operations John Mozeliak, Bader knew his time in St. Louis was over.

“Say it ain’t so, Mo,” Bader said to Mozeliak.

The trade was to New York, 11 miles from where Bader grew up in Bronxville, New York. Bader had idolized Derek Jeter and the Core Four, attending the Yankees’ 2009 playoff run — and when the team hoisted the World Series trophy that year, he imagined one day doing the same. As the news of his new home leaked out on Twitter, Bader’s phone flooded with text messages from friends he graduated with at Horace Mann, a private school in the Bronx. To most of his high school friends, Bader expressed excitement about returning to play for the hometown team.

But to his best friend, Nick Wiener, whom he met in second grade, he expressed frustration.

“I understand why they did it,” Bader told Wiener. “But I’m gonna make them see this was a bad decision.”

There were other complicating factors. Before he ever played a game in pinstripes, Bader faced skepticism from the same fans he once rooted alongside, who wondered why the front office would trade left-handed starting pitcher Jordan Montgomery for Bader, then on the IL with plantar fasciitis and wearing a walking boot.

It didn’t help that the Yankees struggled after the deal, posting a 10-18 record in August, hitting .221/.297/.354 over that span and watching their lead in the division shrink from 15.5 games to four. Montgomery flourished early for St. Louis, allowing just one run in his first 25⅔ innings, good for a 0.35 ERA over four starts.

Meanwhile, all Bader could do was wait to heal — and show up to play when it counted most, down the stretch and into October.

He’s come through. Since making his debut Sept. 20, Bader has won over skeptical Yankees fans, flashing Gold Glove defense in center field. In a hard-fought ALDS that goes to a deciding Game 5 on Monday night in the Bronx, Bader has smacked solo blasts in Game 1 and Game 3 against the Cleveland Guardians before hitting a two-run homer in Game 4, joining Bernie Williams and Mickey Mantle as the only Yankee center fielders with three home runs in a single postseason. They were also his first three home runs as a Yankee.

“Coming to New York,” Bader said, “I felt like I pressed the reset button.”

HARRISON BADER REALLY loved his long hair. He initially grew out his mane in 2018, inspired by players he watched in the NHL, whose flow is visible from underneath their helmets. He loved that his hair made him recognizable. He loved that when he made diving plays in the outfield, it waved around out of his hat like a cape hanging off of Superman. The fans loved it too, with a Twitter account dedicated to his signature locks.

But playing for the Yankees means adhering to the franchise’s infamous grooming policy, which prohibits all players, coaches and male executives from displaying facial hair other than mustaches and growing their hair below the collar.

For Bader, it was symbolic. Hitting the reset button meant cutting off his hair.

“There was not even a thought about it,” Bader said. “It was great, happy to do it. I had a great time on and off the field in St. Louis, and I wouldn’t trade it for anything, but in many ways, this was emblematic of the page turning.”

But even after the haircut, it took weeks for Bader to really process how his life had changed. He sold his home in St. Louis; his mom came and helped pack his life up to move back north. He walked into the Yankee clubhouse for the first time, but still Bader did not fully feel the weight of it all until he finally healed from his injury and returned to the field Sept. 20, the day Aaron Judge hit his 60th homer of the season and the Yankees came back from four runs down in the ninth inning against the Pittsburgh Pirates.

“I don’t think he really processed it until he started going to batting practice and putting on the Yankee uniform,” Wiener said. “He didn’t fully process it until he was out there and making his debut.”

The postseason success has felt like validation for Bader, proof of why he deserves to wear pinstripes, why the Yankees thought it wise to trade for him despite his injury. While Yankees general manager Brian Cashman told Bader that he expected the outfielder to be an impact player for New York, Bader knew fans had questions, and they weren’t the only ones. Montgomery was popular in the Yankees clubhouse, and Bader knew it would take time for him to win over his new teammates, especially given his inability to join them on the field right away.

But Bader knew focusing on things outside of his control would only hamper his ability to succeed on the field.

“You focus on the next thing, the next opportunity,” Bader said. “Then, you kind of relieve yourself of all of the other anxiety.”

IT’S HARD TO miss Bader in the clubhouse. He often dresses like he’s another 20-something New Yorker walking around the streets of SoHo, wearing bright graphic T-shirts and hyped sneakers like the Nike Ben & Jerry’s collaboration Chunky Dunkys, which resell on the secondary market for as much as $5,000. Bader’s new teammates describe him as outgoing, someone who’s always saying hi to the folks around him.

Yankees ace Gerrit Cole noticed Bader’s presence immediately once he joined the team.

“He’s electric, really,” Cole said. “An electric player, impact player. Like, got moxie, got baseball awareness. Gets after the ball on defense. A lot of good things to say about that guy.”

When he joined the Yankees, he also made a mission to get to know fellow outfielder Aaron Judge. While the two needed to get to know each other in order to communicate while roaming for fly balls, Bader also admired the way Judge carried himself on and off the field.

“Bro, not in a weird way, but I want to get close to him and do what he does,” Bader told Wiener. “I’m spending every minute I can next to that man.”

While Bader carried a fiery approach to the game in St. Louis, he saw Judge’s mature and calm demeanor and wanted to adopt it for himself.

“I wanted to surround myself with him and his energy,” Bader said last week. “We move as a unit out there and he’s part of that. It was a conscious decision to just be like, we’re going to be working next to each other so let’s talk. Let’s see where we’re at and just be the best version of ourselves for this team.”

He’s also settled back into New York life, returning to his high school routine of getting a bacon, egg and cheese on a blueberry bagel in the morning, grabbing a slice from his favorite pizza joint (Best Pizza, on First) and attending the wedding of a high school friend, something he would not have been able to do if he was still in St. Louis. He returned to local favorites like Caridad Express, a Dominican restaurant in the Bronx that he goes to with his off-season training partner, Andy Camilo.

Usually on the field, though, Bader tries to show as little emotion as possible, hoping that bottling up his feelings will help propel him to play better. But as his first home run as a Yankee sailed over the left-field fence in Game 1 of the ALDS, Bader couldn’t help but relish the moment, something he spent time visualizing to prepare himself.

“You don’t want to detract from anything that might come later in the game, but it was really hard when everybody was cheering,” Bader said. “It was a great moment. I enjoyed it, and again, as soon as it was over, it’s right back to locking in.”

Bader said this strategy dates back to his time at the University of Florida, where coach Brad Weitzel preached the mindset of “be the baseball,” telling his players that the baseball doesn’t have any emotion, doesn’t take the situation into account, doesn’t care how many fans are in the stands.

“It is totally emotionless,” Bader said. “So I try to act that way.”

Bader knows it’s easy to get distracted wanting to be the hero, hit the big home run, come through in a big moment — especially while playing for your childhood team. Keeping his mind off all that helps Bader on the field — and also helped him off of it, particularly back in August, when he was the new guy who couldn’t help his team win.

“The reality of the situation was that I wasn’t ready to play,” Bader said. “If I was going to force playing, if I was chasing that exact emotion, it wouldn’t have been a version of myself that would have been effective for myself and my teammates. Coping with that reality allowed me to continue to work.”

Even as the Yankees face possible elimination in Game 5, Bader is controlling those emotions again. He doesn’t want to dwell on accomplishing his childhood fantasy for too long.

“It’s a conscious decision every day to not get too high and not get too low,” Bader said. “Everything is just the next opportunity. You have to be completely still and just relax and be emotionless for when that next opportunity arises.”

For Bader and the Yankees, that opportunity is now.