Brandan Craig, Jack McGlynn and Quinn Sullivan are among the pool of 23 players away at training camp for the United States Under-20 team through January 29 in Bradenton, Fla.
The camp is being used as preparation for the FIFA U-20 World Cup, set for May 20-June 11 in Indonesia.
All three Philadelphia Union homegrowns played a big role in qualifying for the competition and winning the Concacaf U-20 Championship last summer.
The Union and Orlando City each have three players on the roster.
Below is the complete roster for the training camp.