Veteran Major League Soccer and U.S. defender Jimmy Conrad retired Thursday, ending his professional career at the age of 34 due to a series of concussions.

Conrad spent the majority of his MLS career with Kansas City and joined Chivas this year for his 13th season in the league. But Conrad, who played 28 games for the U.S., appeared in just two matches this season for Chivas.

"As a player you have this picture of how your career is going to end, maybe a red carpet, fireworks, a statue if you're lucky, but the reality is that it probably doesn't happen that way for 95 percent of athletes," Conrad said.

"So to not be able to go out on my own terms, to say that my last game was a bore-fest against the Colorado Rapids was probably not ideal, not the way I wanted it to go.

"It was a loss too, and obviously you want to go out as a winner, holding the trophy at the very least so that leaves a bitter taste in my mouth."

Conrad debuted in MLS in 1999 with the San Jose Earthquakes (formerly the San Jose Clash) and played 290 matches - including 275 starts - in his career. He finished with 20 goals and 10 assists.

He was selected to the MLS All-Star Team five times, was Best XI nominee four different times, was awarded the Defender of the Year in the MLS in 2005, and represented the U.S. in the FIFA World Cup 2006.

"Jimmy is one of the best assets this league has ever had because he is not only a tremendous player but his work ethic and effervescent personality have always been things that have defined him and he has brought a very big presence to wherever he's been, whether it was with MLS teams or with the national team," Chivas USA coach Robin Fraser said.