Cavan Sullivan, a homegrown player for the Philadelphia Union, made history by starting his first MLS match on July 6, 2025, at Geodis Park in Nashville, Tennessee, becoming the youngest player to start a match in the team's history at just 15 years and 280 days old.

This remarkable debut broke the previous record held by Freddy Adu by 13 days.

Sullivan, who is considered the best product of the Union's youth academy, is the younger brother of Quinn Sullivan, a midfielder for the Union and the U.S. men's national team.

His opportunity for more playing time in MLS has increased following the trade of Daniel Gazdag to Columbus.

Primarily positioned as a central attacking midfielder or right winger, Sullivan has logged 1,632 minutes for Philadelphia Union II in the third-tier MLS Next Pro, scoring seven goals and providing five assists in 26 appearances.

In his debut start, Sullivan played for 60 minutes against Nashville SC, completing 62.5% of his passes while the score remained 0-0 at the time of his substitution.

Overall, Sullivan has played a total of 100 MLS minutes in six appearances during his inaugural season.

In May 2025, he signed a $5 million agreement to join Manchester City once he turns 18, while continuing to play for the Union on loan.

The match was significant as Philadelphia Union was leading the Eastern Conference, just two points ahead of Nashville SC.

The match took place at GEODIS Park, the largest soccer-specific stadium in North America, where Nashville SC was on a 13-game unbeaten run across all competitions.

The Union academy has previously produced notable players such as Brenden and Paxten Aaronson, Auston Trusty, and Mark McKenzie.