The Philadelphia Union announced on Tuesday that midfielder Tranquillo Barnetta will be leaving the club at the end of the 2016 season.
Barnetta, 31, joined the Union from Bundesliga club Schalke and will return to his hometown club St Gallen in the Swiss Super League.
The Union captain has played 37 times in Major League Soccer, scoring six goals and assisting on seven others.
"I'm so thankful to everyone at Philadelphia Union for making me feel so appreciated." -Tranquillo pic.twitter.com/OsT0Nvvl8N
- Philadelphia Union (@PhilaUnion) September 27, 2016
In a statement, Barnetta said: "The entire soccer community here was so welcoming, and I'm so thankful to everyone at Philadelphia Union for making me feel so appreciated.
"Playing in front of my friends and family and making plans for life at the end of my career where I want to live is a force I can't resist."
The Union are in the hunt for a first playoff appearance since 2011, and Barnetta will be with the team to help them see that out. The club sits fourth in the MLS Eastern Conference table and are in a good position to make the postseason.
Former U.S. international and Union sporting director Earnie Stewart said: "Tranquillo has been a key piece in what we're trying to build here in Philadelphia, but we appreciate his decision to return to Switzerland.
"We look forward to continuing to push for the postseason."