Sullivan's impressive form for the Philadelphia Union in MLS has earned him his first call-up for the USMNT. He has seven goals and 12 assists in 26 games for the Union, who have surged up to sixth place in the Eastern Conference in recent weeks. ESPN Soccer reports that Sullivan's stellar form caught the attention of US manager Mauricio Pochettino, who has been "careful" in how he manages the young attacker.
Sullivan's recent form has seen him score six goals and add eight assists in his last eight league games. He made his MLS debut for the Union on July 17, 2024, at 14 years and 293 days old, becoming the youngest player to appear in a league match for a major professional sports league in the U.S. and Canada.
Following the game against Peru, the U.S. will play friendlies against Chile, Mexico and Canada over the course of the September/October international window.