PHILADELPHIA — The Phillies, shortly after a three-game sweep at Citi Field in August, were stuck in traffic. The bus was quiet, interspersed with some laughter, as teammates played cards and tried to leave the mess of a series behind.

Kelly Davis, the head of team security, said he noticed a homeless man outside the bus. He asked the driver to roll down the window and hand the man an extra pizza.

Harrison Bader saw Davis’ gesture.

“I hope that brings good juju,” Bader said to Davis, “because we need it.”

The Phillies returned to Citizens Bank Park. Kyle Schwarber bashed four homers against the Atlanta Braves the next game. Then came a series win against the National League-leading Milwaukee Brewers and a sweep of the New York Mets that cemented the Phillies’ finish atop the NL East. The Phillies have gone 20-9 since that ride back from New York.

So on Fan Appreciation Day, there was something Bader wanted to give away. A row in center field got their own pizzas, on Bader.

“We spread the love, spread the energy,” Bader said. “And we gave (the man) some pizza. So we’re bringing that back to create some good energy moving forward.”

It is just that — good energy — that has allowed Bader to become beloved in less than two months of playing in Philadelphia. His teammates wear a shirt with his motto, “what a gift,” on it. Citizens Bank Park serves “Bader Tots.” He has helped turn the outfield, one of the Phillies’ biggest flaws, into a strength since arriving at the trade deadline. He seems to be the man for this moment for this team.

Harrison Bader does his signature celebration while rounding the bases after a home run. (Emilee Chinn / Getty Images)

With the Phillies, Bader, a 31-year-old who has played for six teams in nine years, capped a regular season in which he set career highs in average, on-base percentage and OPS. Two months ago, he was playing an unnatural position — left field — for a team going nowhere. With one transaction, he received a pair of gifts: playing meaningful baseball and returning to his favorite position, center field.

Bader knew what he was in for when he signed with the Minnesota Twins as a free agent in the winter. Byron Buxton had been their center fielder for more than a decade. So, Bader played left for the first time since college. The routes and reads are different. The position requires more aggression. The first step matters a lot. It took spring training and some early regular-season games, Bader said, but he began to feel better there.

Bader, though, is a natural center fielder. He has known that since he began playing outfield in middle school. Groundballs were a problem, and Bader took many to the face. His dad told him, “Listen you can’t field a groundball. You’re not good at it.” So, Bader ended up in center and first moved to left while at the University of Florida.

After the St. Louis Cardinals drafted Bader in 2015, the club told him he would change positions. Bader was a center fielder, they said. He replied, “I know.”

But what does being a true center fielder mean? For Phillies outfield coach Paco Figueroa, it involves leadership and pride. He sees those qualities in how Bader plays: his footwork, throwing, confidence, routes, jumps.

Some of those traits come from playing left field in college, Bader said.

“I just know the game and just my level of play and my feel, and my routes to the ball, and my decision-making — I’m a center fielder,” Bader said. “But my junior year, I played left. So it was good because that gave me a good foundation for understanding fly balls and how they’re struck off the bat. Because in center field, you’re exposed to more of a true read.

Everything’s in front of you, so all of your reads, the balls you run down, are right in front of you. Obviously, in left field, you’re offset. It’s just a different visual perception. It actually made me a more rounded outfielder playing that position at a younger age, which, in turn, was more beneficial for my career because I just saw the game better.”

It was unclear where the Phillies would use Bader when he arrived via trade on July 31. They settled on center, though it took some shuffling in August before Bader won an everyday role in September. He has helped save an outfield that, just two months ago, was a problem. The group still ranked among the worst in MLB in Defensive Runs Saved (minus-17) and outs above average (minus-9). Bader, a Gold Glove center fielder who is among MLB’s top outfielders in OAA (six) and DRS (14), has brought stability and swagger.

Bader first saw more playing time on the trip to Milwaukee earlier this month. That when it first hit outfielder Max Kepler: This guy is very good at his job.

“The one in Milwaukee (on Sept. 4), he leaped up and it was for the second out,” Kepler said. “I was in right. It was that shadow game. And he jumped right into that stream of sunshine and made a nasty play up on the wall. And I was like, ‘Holy s —.’”

“He jumped right into that stream of sunshine and made a nasty play up on the wall,” Max Kepler said of Harrison Bader’s highlight catch in Milwaukee. (Patrick McDermott / Getty Images)

There have been other memorable defensive moments, too. A leaping home run robbery at the wall in Texas is Figueroa’s favorite. Bader also quickly played a ball hit off Monty’s Angle at Citizens Bank Park in August, holding J.P. Crawford to a double — an angle Bader said he’d like to avoid if possible because “it is funky.”

Bader provided an offensive spark at the beginning of September, too, as he slashed .381/.418/.571 with a .989 OPS in his first 15 games. He’s cooled somewhat. It makes some sense. His career OPS is .714, and his season OPS is .796.

There is plenty Bader brings on paper. But his most valuable trait seems to be the intangibles. Energy is the word everyone uses when talking about him. What does it look like in action?

“You’ve talked to him,” Kepler said. “You’ve seen the crowd. He always seems to be smiling, cracking jokes and approaching you. Like, if I’m just hanging out at my locker, he’ll come (and) bring some type of topic up. He brings good energy with it.”

“I like the fearlessness that he has out there,” Brandon Marsh said. “I see a free gazelle when I watch him play, and that’s what you want out of your outfield — especially your center fielder.”

Harrison Bader rises to rob a home run against the Rangers in August. (Ron Jenkins / Getty Images)

There is something unique about watching Bader play at Citizens Bank Park. It could be the bright, purple and pink gear he wears. Or his dominant defensive skill set. His trot backward before catching a fly ball is part of it.

The move, which Bader has done throughout his career, now has a name: “El Cangrejo,” or the crab. Figueroa, a couple of weeks into Bader’s tenure, began calling it that because of the resemblance to how a crab moves. It is about getting behind a fly ball and building momentum through it, Figueroa said, making it easier for Bader to try to prevent a base runner from advancing.

It is a move similar to what many players do. Bader’s version is just much more drawn-out.

“That’s him, though,” Kepler said. “That’s what makes him him.”

“He’s one of one,” Marsh said. “He does it well, so he needs to keep doing it.”

Harrison Bader, with Edmundo Sosa and Alec Bohm, at the center of another Phillies celebration. (Mitchell Leff / Getty Images)

Everything seems to be contagious with Bader — even the crab walk. Kepler said he’ll catch himself backpedaling in the outfield now.

The phrase “what a gift” quickly caught on, too. Manager Rob Thomson referenced it when toasting Schwarber for reaching 50 home runs. Phillies players wear their “what a gift” T-shirts to batting practice. Bader sometimes raises his arms while saying it — an action Edmundo Sosa seemingly emulated when rounding the bases after hitting a home run last week.

It is a phrase dating back to Bader’s time in St. Louis, a way he’s found to turn any negative experience into a positive. He says it after pretty much every hit and defensive play and his teammates’ positive plays.

“Like sitting in traffic, I’m late: What a gift,” Bader said. “I think it just kind of shifts the energy immediately. And I think that’s important to keep the positive energy going because energy is everything in life, especially this game. ‘What a gift’ is just an easy saying to kind of bring you back to neutral.”

Bader sailed across home plate, arms raised, to score the winning run in Game 162 on Sunday. He joined the group mobbing Nick Castellanos and celebrated one last regular-season win. Now, Bader is on to the gift of postseason baseball — and with his catchphrase tattooed on his left forearm. He got it during the offseason.

“It’s meant to be,” Bader said.

— The Athletic’s Matt Gelb contributed to this report.

(Top photo: Emilee Chinn / Getty Images)