Foxborough, MA (SportsNetwork.com) - Former D.C. United and New England Revolution midfielder Clyde Simms called time on a nine-year MLS playing career on Thursday, announcing his retirement due to health concerns.

"I've never really talked about this because I always chose the mind over matter approach, but my health has gotten to a point where I can no longer do that," Simms said in a statement. "When I was a freshman in high school, we discovered that I suffered from Focal Segmental Glomerulosclerosis (FSGS), the same kidney disease as Alonzo Mourning. When I started playing with D.C., my kidney function was around 50 percent, and the last three years of my career, it has gotten down to about 20 percent.

"I fell in love with this sport at a young age and was determined not to let anything stop me. Unfortunately, for the past 10 years I have been dealing with kidney disease and it has become too tough for me to compete at this level anymore. I made sure for as long as I could I would still fight for my dream, my passion. I was very lucky to have had such a great run, but now it's time to fight another battle. Thank you to all the fans, teammates, and coaches that supported me and helped me along my journey. To the Richmond Kickers, D.C. United and the New England Revolution, thank you for allowing me to be a part of your families. I will always be a fan. And to my family and people closest to me, thank you for allowing me to follow my dream."

The 31-year-old began his MLS career in 2005 with D.C. United after signing from the Richmond Kickers. He made 182 appearances in his seven seasons with United, fifth-most in club history.

Simms entered the Re-Entry Process in December 2011 and signed for New England where he went on to make 39 appearances - and 38 starts - in two seasons.