The 29-year-old Kearns hit only .195 with three homers and 17 RBIs in 174 at-bats this season, when he was hampered by a thumb problem. Elbow and foot injuries limited Kearns to 86 games in 2008, when he batted .217 with seven homers and 32 RBIs.
In 2007, his only full season in Washington, Kearns hit .266 with 16 homers and 74 RBIs.
He joined the Nationals in a midseason trade with the Reds in 2006. On Feb. 1, 2007, the Nationals announced a three-year deal that paid Kearns $17.5 million, including the buyout.