Cincinnati Reds' Adam Dunn, right, is congratulated by teammate Aaron Boone, left, after Dunn hit a two-run home run in the ninth inning against the Chicago Cubs, Thursday, Sept. 20, 2001, in Cincinnati. Chicago won 6-5.

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Cincinnati Reds Ken Griffey Jr. jumps on the back of Adam Dunn (44) after Dunn hit a three-run home run off Milwaukee Brewers pitcher Dan Kolb in the 11th inning on Wednesday, June 14, 2006, in Cincinnati. Cincinnati won 3-0. (AP Photo/David Kohl)

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Washington Nationals Adam Dunn, left, and batting coach Rick Eckstein, right, look on after Dunn struck out against the San Diego Padres.

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Washington Nationals' Adam Dunn, right, argues with first base umpire Tim McClelland on a called strike on Friday, April 16, 2010, in Washington. Dunn was ejected.

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Washington Nationals' Adam Dunn swings for an RBI sacrifice fly against the San Francisco Giants Tuesday, May 25, 2010, in San Francisco.

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Cincinnati Reds outfielders Adam Dunn, left, and Josh Hamilton run off the field during a baseball game against the Houston Astros, Monday, May 7, 2007, in Cincinnati.

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Cleveland Indians catcher Kelly Shoppach, right, holds on to the ball after tagging out Cincinnati Reds' Adam Dunn on Sunday, June 29, 2008, in Cleveland.

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Washington Nationals' Adam Dunn follows the flight of his solo home run against the Colorado Rockies on Saturday, May 15, 2010.

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Cincinnati Reds' Jerry Hairston Jr., (15) is picked up from home plate by Adam Dunn (44) after Hairston Jr. , Saturday, July 5, 2008 in Cincinnati.

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Washington Nationals' Adam Dunn follows the ball as umpire Tim Timmons and Baltimore Orioles catcher Matt Wieters look on .

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Washington Nationals first baseman Adam Dunn (44) in action against the Cincinnati Reds.

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Washington Nationals first baseman Adam Dunn (44) slides safely into third on a wild pitch as San Francisco Giants third baseman Pablo Sandoval, right, waits for the ball.

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Washington Nationals first baseman Adam Dunn (44) looks out from the dugout before a baseball game against the Philadelphia Phillies.

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Washington Nationals Adam Dunn (44) tips his hat after hitting his third home run against the San Diego Padres in Washington, Wednesday, July 7, 2010. The Nationals beat the Padres, 7-6.

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Washington Nationals first baseman Adam Dunn (44) in action against the Cincinnati Reds.

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Washington Nationals' Adam Dunn, right, runs to third base on a ball hit by Nationals' Josh Willingham .

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Washington Nationals' Adam Dunn blows a bubble on the on-deck circle during the sixth inning of a baseball game against the San Francisco Giants.

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Washington Nationals' Adam Dunn rounds third base after hitting a two-run home run during the sixth inning of a baseball game against the Philadelphia Phillies.

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Washington Nationals' Adam Dunn, right, hits a three-run home run to also drive in teammates Ryan Zimmerman and Ian Desmond as Los Angeles Dodgers catcher Brad Ausmus, left, looks on.

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Washington Nationals first baseman Adam Dunn (44) plays in the baseball game between the Pittsburgh Pirates and the Washington Nationals in Pittsburgh, Friday, Sept. 3, 2010.

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Washington Nationals first baseman Adam Dunn blows a bubble during the seventh inning of a baseball game, Saturday, Sept. 11, 2010, in Washington.

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