Joe Scally will move to Borussia Monchengladbach once he turns 18 on Dec. 31, 2020. Noah K. Murray-USA TODAY Sports

When Joe Scally was 14, his youth coaches at New York City FC moved him from central midfielder to right-back. On the field, the distance amounted to about 25 yards, give or take. Two years on, it's set to translate into a journey of thousands of miles, and for NYCFC, it could well turn into a quantum leap.

Scally, now 16, has been transferred to German side and Bundesliga leaders Borussia Monchengladbach. Sources tell ESPN that the initial fee is around $2 million, with add-ons in the form of "very achievable appearance bonuses" that could take the final fee to as high as $7 million. There is a sell-on fee as well, although that will decrease as Scally gets more minutes on the field. Because Scally doesn't have a European passport, he will remain with NYCFC through next season and then join Gladbach midway through the 2020-21 European campaign after he turns 18 (his birthday is Dec. 31).

Scally is described by those who have followed his time with NYCFC as very athletic with the kind of mobility that allows him to get up and down the flank. While his defending needs work, his ability to contribute in attack is what sets him apart. His forward skills were evident at the recent FIFA U-17 World Cup, when his cross set up Gianluca Busio for a goal against Senegal.

"[Scally] is a very modern outside back who can cover the whole outside [flank]," said NYCFC sporting director Claudio Reyna. "He's a right-back who creates and has a lot of assists."

The deal amounts to a first of sorts in MLS, as it was completed before Scally had played any first-team minutes in league play for NYCFC (he did appear in a U.S. Open Cup match in 2018). It's similar to Chris Richards' move from FC Dallas to Bayern Munich in 2018, although in Richards' case, he was initially loaned out before securing a permanent move earlier this year.

So why move Scally now instead of waiting to see if he can prove himself in NYCFC's first team? It's a simple case of everything being in alignment.

"There comes a point where there's a deal on the table that's just too good to pass up," Reyna said. "[Gladbach] stepped up, made an offer. It's just a great deal for us. Sometimes you're not quite sure if you're selling at that right value. We look at data from around the world for similar transfers, and so we want to make sure that we're in the same ballpark and that we're not asking for a ridiculous transfer fee. There is also a point where their value starts dropping, and you have to be aware of that. So you have to kind of strike while it's hot, and that's what happened with Joe. It just made so much sense."

For Scally, it's the realization of his dream to sign with a team in one of the top five leagues in Europe, although the pathway was a bit fuzzy when he first made the positional switch to right-back. Scally was playing with NYCFC's U15 team at the time, and nominal right-back Nico Benalcazar -- now a freshman at Wake Forest -- was away on international duty. Then-NYCFC youth coach Rodrigo Marion had been impressed with Scally's size, speed and passing, so he played Scally at right-back, and he performed well enough to make the move permanent, even though there was some resistance.

"At first I was like, 'No way would I want to do this,' because I've always liked scoring and assisting on goals and everything," Scally said. "Then I realized it could be the best position for me, and this could bring me to another level if I kept progressing at this position."

NYCFC soon moved Scally to play with the club's U19 team, helping it win back-to-back U.S. Development Academy titles; those performances enabled him to sign a homegrown contract. Gladbach took notice as well, especially as Scally began playing for U.S youth national teams.

"We were surprised," said NYCFC technical director David Lee about Gladbach's interest. "We all knew how good Joe is and why we signed him so early on in his career. But I definitely don't think we were expecting any team to come in and buy him at this point in his development, purely because it isn't particularly normal in MLS and the U.S. for that to happen."

Initially, Scally's lack of a European passport meant negotiations were moved to the back burner, but they reignited about eight months ago and eventually resulted in a deal. "Their interest kept growing and growing," Scally said. "It became like, 'Wow, this could be an opportunity for me to go to Europe.' As I got older, and now I'm 16, we went over there and saw everything. It made me realize that this is the place that I want to play at."

It's a massive step for Scally -- although he will have the benefit of another season with NYCFC -- and his family as well. That said, it's similar to the kind of separation that takes place for a lot of parents with children in their late teenage years. "My mom says she's going to miss me every day," Scally said. "My dad, of course, he's always just telling me that it's a great opportunity and I'm going to love it there. They treat it as if I'm going away to college."

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Overall, Scally's move amounts to another success for NYCFC's academy. While MLS teams like FC Dallas, Real Salt Lake, the Philadelphia Union and the New York Red Bulls remain at the top of the heap in terms of players produced, it's worth noting that NYCFC's academy has only been around since 2014. And now there are a variety of stories to tell.

Defender James Sands, 19, made 19 league appearances this season. Eighteen-year-old midfielder Justin Haak has gotten a taste of first-team action with six league and cup appearances, as well as leading the U19 team. Now Scally is making the move overseas. It's one thing to say there's a path from the academy to the first team. It's another to offer up actual proof.

"We obviously don't have a traditional pipeline in MLS," said NYCFC academy director Sam Pugsley. "We don't have a second team, but what we've been able to build here is something we believe in, in a very short period of time, to be successful. And I think anytime you can put it in a PowerPoint or a piece of paper and show tangible evidence of that pipeline coming to fruition, it helps the sell to players and parents."

Scally's story is one that Reyna wishes more of his MLS colleagues would replicate. It's only in recent years that MLS has begun to engage more in the international transfer market as both a buyer and a seller. But actual transfers for academy products, as opposed to players leaving for free, is a new phenomenon, and a move like Scally's is one that Reyna believes "brings a lot of credibility to our league." It will increase European scouting of American players, and as there are more success stories, the value of youth players will go up.

Reyna sounded almost exasperated as to why there isn't a greater willingness on the part of MLS clubs to sell youth players like Scally, assuming the desires of the selling club, the buying club and the player all align.

"There's sometimes some sensitivity to [selling young players] here, and I don't understand why," he said. "If you go to Holland or Germany or Portugal or Italy, for that matter, if you're not the biggest club in that country, you're very open to telling a player that at some point, if they're doing well, they'll move on to perhaps a bigger club and a bigger stage. Countries and leagues that have been around much longer than us have been doing this. I don't really know why we wouldn't act in the same way."

Every club is different, but as academies in MLS and beyond become more mature, it seems only a matter of time until their players are involved in deals like Scally's.

For Scally and NYCFC, that time is now.