Washington was a weakhitting team last season, and Dunn has hit at least 40 home runs in his last five seasons. Among active major-leaguers younger than 30, only one, Albert Pujols (319), has more home runs than Dunn's 278.

Dunn, a left-handed slugger, was once a favorite with the Reds, but last season he was often criticized for poor defensive play as a left fielder, low batting averages and too many strikeouts. But former Reds All-Star shortstop Barry Larkin likes the Nationals move.

"Jim Bowden has been eyeing Adam Dunn for a long time," said Larkin, a teammate of Dunn's in Cincinnati and a Washington front office member from 2005 until 2008. "You will see a lot of long, high home runs. Strap up your boots, because this guy can hit 'em. And that's an excitement that has not yet been seen in Washington."

Meanwhile, the Reds have not signed anyone to replace the power void left by Dunn's departure. The franchise has young, potential power hitters in first baseman Joey Votto, who hit 24 home runs last season, and outfielder Jay Bruce, who hit 21 homers. Also third baseman Edwin Encarnacion hit 26 home runs and second baseman Brandon Phillips hit 21.