Sources close to the matter have confirmed that Sullivan will be part of the USMNT squad set to face Peru, Chile, Mexico, and Canada over the course of the window. The official announcement is scheduled to take place on September 17. Sullivan's recent form has caught the attention of USMNT manager Mauricio Pochettino, who has been impressed by the teenager's goal-scoring and assist record since the resumption of play following the MLS break.

Sullivan has scored six goals and added eight assists in his last seven league games, and has now netted nine goals and 15 assists across all competitions this season. The Philadelphia native has long been touted as a future star for the USMNT, having signed a homegrown deal with the Philadelphia Union at the age of 14.

Sullivan will be the second-youngest player to play for the USMNT if he makes his debut in any of the upcoming matches, behind only Freddy Adu, who first appeared for the USMNT at 16 years, 243 days when he came on as a substitute in a 0-0 draw against Canada on January 22, 2006. The USMNT's first game is against Peru on September 26 in Orlando, Florida.