"Dear Softball, it’s time this intimate relationship we’ve had ends. It’s not you… it’s me. You’ve had my heart for 28 years, and now I need it back, to invest it elsewhere," Osterman wrote in an Instagram post. "New experiences, my family, and cheering on everyone else who loves you."
The 38-year-old pitcher helped Team USA to the Olympic title at the 2004 Olympic Games in Athens. She was part of the U.S.'s silver medal-winning teams at Beijing 2008 and this past summer at Tokyo 2020.
Osterman had first announced her retirement in 2015, but came back to the sport in 2019 as softball prepared for its return to the Games after not being part of the Olympic programme for London 2012 or Rio 2016.
In addition to her Olympic medals, Osterman was part of Team USA's winning efforts at three Pan American Games (2003, 2007, 2019) and two World Championships (2006, 2010). She's been a member of the U.S. national team for 13 seasons.
“This is the start of a new chapter for one of the greatest competitors, pitchers, representatives of softball, and one of the greatest people to ever wear the USA uniform,” said Ken Eriksen, who coached Osterman in Tokyo, according to statement from USA Softball.
“Cat’s career has had an impact on the way the game has been viewed by both women and men. She has left an indelible mark on the game as well as on many people across the country. I have been one of the luckiest people to have been around her all these years while witnessing her historic career.”