Young played in only 50 games this year, batting .280 with four homers and 10 RBIs in 150 at-bats. He missed time with a lower back injury and while receiving treatment for diabetes. He was shut down for the season after straining his left hip while running the bases during a minor league rehab assignment in early September.
Young resurrected his career with the Nationals in 2007, coming back from personal, professional, legal and substance abuse problems to hit .320 and earn a spot in the All-Star Game.
Washington rewarded Young with a $10 million, two-year contract extension through the 2009 season. Young could have refused the Triple-A assignment and become a free agent, but he would've forfeited the final year on his deal, which is worth $5 million.
"I have a great deal of respect for the Nationals organization and the opportunities that they have provided me," Young said in a statement issued through his agent, Adam Katz. "As such, I have accepted the assignment. I look forward to the challenge of battling my way back and making a meaningful contribution to what I expect will be an exciting team in 2009."