When the Union opened their own high school in September of 2013 on the campus of YSC Sports in Wayne, fans with high hopes for the team's future wondered how long it would take for the program to develop pro prospects.

It looks like the answer might be "not very."

Fewer than two years after the school launched, Union manager Jim Curtin judged some of the school's players to be worth bringing along with the big club on its preseason training trip to Clearwater.

And so far, according to Curtin, it looks like the kids - in particular a quartet of 17-year-olds - are holding their own.

Leading the way so far has been Derrick Jones Amanimpong, a 6-foot-3 defensive midfielder who was born in Ghana. After moving to Philadelphia, he played for the Southwest Philadelphia-based Junior Lone Star club, which has a history of bringing in African immigrants and developing their skills.

"He's a player that I am very high on [and] absolutely has a chance of making the team," Curtin said. "You can't coach 6-foot-3 and having good feet… Having him in for this 12 to 14 day block will be critical for his development."

Another player who has impressed Curtin is forward Yosef Samuel, a forward from Atlanta. Curtin said Samuel has "shown he belongs" and "is close" to being at a pro level.

"He's going to be a pro, it's just a matter of a timeline," Curtin said. "We'll make a decision at the end of [preseason]."

The Union academy's most-touted prospect of all, striker Sebastian Elney, isn't with the team right now. But his absence is for a good reason: he's been with the United States under-18 national team at the Copa Chivas tournament in Guadajalara, Mexico.

Elney started and captained the U.S. squad in three of its four group stage games. The U.S. didn't make it out of the group, so it played a friendly against another non-qualifier on Thursday, and Elney scored a goal in that game. Now he's headed to Clearwater to join the Union.

"He's a top striker in our country in his age group," Curtin said. "I've seen him up close live and he has all the tools to be a good striker in our league."

But as with all young players, there's a learning curve when they reach the big leagues. Indeed, the same can be said of another Philadelphia team that's training near the Union's home for this month. The Phillies' Bright House Field complex is directly across the street from the Union's training facility.

"[Elney] has learn to do it for 90 minutes," Curtin said. "I think he picks his moments in games when he wants to take over, and he gets away with that at the younger age group because he can dominate that group... As he gets thrown in with our first team, it's not as easy for him, and he has to rise up to the level."

Another Union academy player who's been with the U.S. U-18s, midfielder Sean Wilson, is also headed to Clearwater. He started in three of the four Copa Chivas games, going all 90 minutes in two, and was a substitute in the other one.

Though the Union's future looks bright, the present looks a bit cloudy. Negotiations are in final stages to send defender Carlos Valdés to Uruguayan club Nacional, a move that will free up roster space for the team to sign an experienced replacement. But they're dragging, and that has caused some frustration for the Union and its fans.

Curtin had to be somewhat coy in his remarks given the ongoing talks, but he expressed hope that the deal gets done soon.

"[Valdés is] at the point of his career where now financially he's looking to make his family comfortable, to be quite honest," Curtin said. "I want to coach the guys that fully are going to be here, and that's kind of controlling what I can control. Our relationship is the same, but at the same time I have to move forward as a coach."

Curtin said his talks with Valdés have been amicable, and that "we will do what is best for the Philadelphia Union and for the player."

As for the Union's attack, they missed out on signing one of their main targets, Wigan striker Andy Delort. He chose instead to return to his native France on a loan to Tours, the club which sold him to Wigan. So the Union must turn to backup plans to boost the forward corps.

Curtin said he has been impressed by his current players' performances in scrimmages - especially draft pick Dzenan Catic - but that "doesn't mean we aren't going to add a piece up top."

"We have targets and are actively pursuing them," Curtin said. "It's by no means a finished product."

If attacking reinforcements do come, they might not be of the kind who would directly replace veteran big man Conor Casey.

Although Curtin admitted that "we rode Conor too much" last year, he added that a new signing "may be a different type of striker," perhaps with a greater emphasis on speed than size.

"You want to find the right mix," Curtin said. "You don't want to have three or four of the same type of forward."

Between Casey, the 6-foot-3 Catic and 6-foot-1 new signing C.J. Sapong, the Union's forward corps does already have its share of size. Sapong in particular is expected to play a key role this year, whether in the middle or in a wider position.

Elsewhere on the field, the Union welcomed two new international trialists: 30-year-old Greek left back Petros Kanakoudis, most recently of Greek first division club Kerkyra; and 18-year old Iranian attacking midfielder Navid Nasseri, most recently of Birmingham City. Nasseri already has experience with Iran's Under-21 national team.

Curtin spoke highly of both players' technical skills, but said he won't be able to get the true measure of them until he sees them in a live game. The opportunity do so may come this weekend, when the Union plays its first preseason game of the year. They'll visit the Jacksonville Armada, an expansion team in the second-tier NASL. It will be the Armada's first ever game as they prepare for their debut season.

Kickoff at EverBank Field, home of the NFL's Jaguars, is set for 5:30 p.m. My understanding is that the game will be streamed online, but not all of the details have been worked out yet. As soon as I have confirmation, I'll pass it along.