Dillon Serna is probably the most exciting prospect to be inside of the Colorado Rapids academy system... well, ever. Davy Armstrong is the only one from the academy system currently on the squad, but Serna is getting quite a bit of work from the US national team, which Armstrong can't claim.
Most recently, the young Rapids academy midfielder was named to the US U-18 squad headed to the four team Lisbon International Tournament. The U-18 team doesn't do any international competitions so friendlies and small tournaments like that are the only way to get real exposure in that side. He was able to earn a full 90 minutes of time in the USA's 0-0 draw against 10 man Slovakia, where the US dominated possession and shots.
Serna had gotten looks from the U-17 team as well and will hopefully progress to the U-20 team if his time with the U-18 squad continues to go well and he continues to get time.