Brenden Aaronson

Leeds United are among the many clubs seriously interested in ex-Philadelphia Union and current US men's national team midfielder Brenden Aaronson, sources tell MLSsoccer.com. As previously reported, AC Milan and RB Leipzig remain in the chase for the current Red Bull Salzburg star as well.

With RB Salzburg advancing to the UEFA Champions League Round of 16 against Bayern Munich, it is highly unlikely a transfer would happen this winter. Aaronson is among Salzburg's best and most important players.

Leeds play a full-throttle pressing system under Marcelo Bielsa and have former New York City FC star Jack Harrison on their roster. Leipzig were previously managed by American and former Salzburg boss Jesse Marsch, though parted ways with him in early December. Milan currently sit second in Italy's Serie A, with former LA Galaxy striker Zlatan Ibrahimovic leading the way.

Aaronson staying put a little longer would benefit the Union as well.

The Union academy product joined Salzburg for an initial $6.5 million fee last January, with incentives potentially taking the fee to $9 million. Sources say those incentives are virtually guaranteed to 100% hit if Aaronson remains with Salzburg until the summer, meaning the Union would receive every dollar of the potential $9 million.

Philly also retain a sell-on clause for Aaronson that is tiered between 10-20% depending on the next transfer fee, which won't be cheap.

Aaronson, 21, has been a leading light for Salzburg as well as the USMNT. This year he has started all six Champions League matches and both qualifying games, where he had two goals and an assistant to help Salzburg qualify. He has a goal and five assists in 16 league appearances this season as Salzburg sit atop the Austrian Bundesliga, already with a 14-point cushion in first place.

Since joining Salzburg, Aaronson has been an integral player. He has 10 goals and 12 assists in 51 appearances across all competitions, while he's now up to 15 caps with the USMNT.

Aaronson made his MLS debut with Philly in 2019 and broke out in 2020, helping lead the Union to win the Supporters' Shield, their first-ever trophy. He was also named MLS Best XI that year.