The last time Christian Pulisic came to Philadelphia with the U.S. men's soccer team, his professional career had only just begun. It was the Copa América Centenario, and the Hershey native had just one season at Borussia Dortmund under his belt.

Now he's more than a teenage phenom. He's a well-established presence at Dortmund, a centerpiece of the U.S. national team, and increasingly famous on the overall sports landscape. Just ask LeBron James, who recently sent Pulisic a pair of game-worn shoes.

(There was no word on whether Pulisic, a Sixers fan, tried to recruit James to Philadelphia in return.)

Pulisic knows full well just how much he has grown during the past two years.

"I've developed so much as a player since then — I've had so many more experiences over in Europe, and also with the national team," he said. "Slowly getting more and more minutes, and experiencing things and learning more about the game and about myself. I feel like a much more developed and confident player."

Monday's game against Bolivia at Talen Energy Stadium (6:55 p.m., Fox Sports 1 and UniMás) will be the first time Pulisic plays for the national team in his home state. He didn't get on the field in the Copa América game two years ago.

More important, it will be the first time Pulisic teams up with Weston McKennie in the center of midfield for the senior national team. They were teammates as kids going back to the under-14 level. Now they've made it to the big time. Their partnership has the potential to be the heart of the national team for years to come.

"I'm really excited," Pulisic said. "To play with him now on the full men's national team, it's definitely an exciting time. I'm definitely looking forward to it."

McKennie is just as amped.

"Knowing him for such a long time, but not really having the chance to play with him [at the senior level] … I think it will be exciting not only for me, but I think for a lot of people, too," he said.

Pulisic and McKennie know each other not just from their youth national team days, but from a bond in the present, too. They both ply their club trades in Germany's industrial heartland.

And there's a little extra spice from being on opposite sides of one of the Bundesliga's signature rivalries: the Revierderby between Pulisic's Dortmund and McKennie's Schalke 04. The players' first game against each other was a wild 4-4 draw at Dortmund last November.

"It's like nothing I've ever seen before," McKennie said. "It's mind-blowing if you experience it."

Pulisic has lived in Dortmund for more than three years now. If he leaves anytime soon, it will be because another European club writes a big check to sign him.

But he still considers his home to be where it has always been.

"America will always seem like home to me," he said. "As much as I love Dortmund [and] being in Europe, here is always home."

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Weston McKennie looking to build on impressive U.S. national team debut

Cameron Carter-Vickers' rise to U.S. national team has been in the works for years

Christian Pulisic, at 19, is one of the most experienced players on a USMNT squad looking for leaders

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