Mueller’s decision carries extra weight because of everything that came before it. He missed the 2025 season after being diagnosed with pericarditis, then worked his way back and reappeared in pre-season against LA Galaxy. He would go on to make five league appearances for Chicago this year, including one start.
In his statement, Mueller also thanked the club for bringing him home and for standing by him during his illness. That matters. Retirement stories often focus on numbers, but this one feels more personal: a player trying to get back, doing so, and then deciding the right moment had come.
Mueller joined Chicago Fire in 2022, returning to represent the club he had supported as a child in Illinois. The club says he made 66 appearances, scoring six goals and adding 10 assists.
Before that came the most productive stretch of his senior career at Orlando City, where he grew from lively MLS attacker into a genuine difference-maker. His move to Hibernian did not fully catch fire, but it still added a valuable chapter abroad before he returned home.
Mueller’s international career was brief, but memorable. He won two caps for the United States men’s national team and scored both of his international goals in a 6-0 friendly win over El Salvador in 2020. For any player, that is a moment to keep forever.
What comes next is worth watching. Chicago must now move forward without a popular squad figure, while Mueller, still only 30, appears set to begin a new chapter with the goodwill of every club he touched along the way.