In retrospect, Keegan Rosenberry could’ve seen it as a sign of something good.

Participating in a match to help USMNT reserves stay fit during the Copa America Centenario, Rosenberry wasn’t slotted with his Philadelphia teammates; The right back was plugged in behind winger Christian Pulisic for the U.S. side.

“At first I kinda thought it was a coincidence,” Rosenberry said. “What a chance to hopefully show well. But the more people I talked to, it seemed they wanted to get a proper look at me. As the season progressed, I didn’t think too much of it.”

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Still, that was one of just two experiences with the U.S. set-up. Rosenberry had not represented the Americans at any level when he was called up for a U-23 camp for college players only, listed as a midfielder, in 2015.

In the short period since, Rosenberry has grown into a player pegged as a to get a USMNT look under Bruce Arena, something the coach confirmed in a Facebook Q&A last week.

“I’m obviously very, very excited to even be in the discussion,” he said. “I can’t wait.”

Neither can U.S. fans eager to see how Rosenberry compares to DeAndre Yedlin and other options on the right. That’s pretty remarkable considering the right back showed up at Georgetown in 2011 at a different position.

“He was always playing as a center mid,” said Georgetown head coach Brian Wiese. “But my assistant, Zach Samol, saw him first and said he loved this kid because he’s so technical. He’s very clean, tough, quick. He tackles. He makes good decisions with the ball, and has good spring for not being a 6-foot kid, and his habits are really good.”

Wiese says Rosenberry became a right back by virtue of positional need. The Hoyas wanted him on the pitch, but had MLS prospects up-and-down the center of the park. Their holes going into Rosenberry’s freshman year were striker, center back and right back, and they filled them pretty well: Brandon Allen at striker (now with RBNY), Cole Seiler at center back (Vancouver), and Rosenberry on the right.

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“At first it was a shock to my confidence because I played all my life in the middle, and I fancied myself there,” Rosenberry said. “To hear that (he’d play right back), it wasn’t the first thing I wanted to see. But then I saw the talent of the players on the team, and I thought if I could get on the field I’d play any position.”

He started every match of his four years at Georgetown and captaining the club the last two seasons. The Hoyas went to the national championship game in Rosenberry’s freshman year, and went to the third round twice and quarterfinals once in his final three seasons.

“That experience in college was so important because I felt like I was still developing physically and mentally,” Rosenberry said. “Being a captain there for a couple of years and trying to manage the personalities and egos and demands of 25 guys really helps you mature whether you like it or not, and it makes you be a leader. It was something that I really valued.”

Rosenberry and Georgetown teammate Joshua Yaro were both selected by Philadelphia in the Top Three of this year’s SuperDraft. To wind up with Philadelphia was a boon for the Harrisburg, Penn., native. Rosenberry wasn’t a member of the Union’s Academy but had trained with now head coach Jim Curtin, and he admired the boss. He was inspired to put on the shirt.

Rosenberry played every minute for Curtin’s unit this season, completing almost 300 more passes than anyone on the team. Only attack-minded players Tranquillo Barnetta and Seb Le Toux completed more key passes than the rookie.

“Going to team like Philadelphia who I was familiar with before the draft, knowing some of the staff and some of the players and where to go for training, it makes you feel like you belong and I think it helped me with the transition period,” Rosenberry said. “I’m really thankful for that.”

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He admits a sour taste from bowing out to Toronto FC in the first round of the playoffs, but Jim Curtin’s Union wasn’t expected to make the postseason this season. Rosenberry was a big part of the surprise, his work earning him a nod as a finalist for the MLS Rookie of the Year award ultimately claimed by Jordan Morris.

Before the Union begin their follow-up run in MLS, Rosenberry will — barring a dramatic turn of events — represent the United States men’s national team at January camp under Bruce Arena.

Wiese sees a comparison between Rosenberry and a current USMNT player that the Georgetown coach helped recruit as an assistant at Notre Dame in 2005: Matt Besler.

There’s a natural comparison of the two players. Besler is taller, and Rosenberry a bit quicker, but both are praised for their inherent leadership and speak about the game in an analytical way.

“There’s just a real quality in both of those guys,” Wiese said. “There’s an underlying current of quality in everything they do, in terms of how they manage themselves, train, take care of their bodies, how serious they are about their approach to their craft and you’re like, yeah, of course they’re going to make it. Those are two guys you never have to ask to do anything twice. You never need to bring them into the office to chastise them for doing something off the field.”

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While Rosenberry says there was a chance he’d have to fill in at center mid following deep injuries to Philadelphia’s corps, he expect he’s a right back for life right now. And he’s grateful chance put him in that position once he left his youth club, Penn Fusion, for college in Washington, D.C.

“I took it as a challenge to hone myself as a better 1v1 defender and all the traits that come with the position,” he said. “The similarities between center mid and right back might not be too far off in terms of distribution and connecting passes and whatnot. Where it’s different is getting exposed as a defender 1-on-1 and trying to deny service where in the middle you’re maybe trying to slow things down, stop counter attacks, or funnel things one way or another. Interestingly enough, I think it made me more marketable. There are 3-5 midfielders on the field at all times, but there’s only one right back. From my sophomore year on, I viewed myself as a right back.”

And U.S. fans may be viewing him there for a while. Bring on January.

Follow @NicholasMendola