on August 21, 2009, after hitting .322 with 16 homers and 86 RBI in 110 minor league games. In 2010 with the Nationals, Morse played 98 games and batted .289 with a .352 on-base percentage and a .519 slugging percentage, with 15 home runs and 41 RBIs. In 2011 spring training, Morse led the Grapefruit League with nine home runs with 18 RBI. He started the 2011 regular season in a left field platoon with Laynce Nix, but slumped on offense and was relegated mostly to pinch hitting by May. However, on May 22, 2011, Morse moved to first base when Adam LaRoche's season was ended by injury. In his first four games at first base, Morse hit three home runs with eight RBI. From May 22 to July 5, Morse had 13 home runs and 35 RBI, the most in the majors in that span of time, earning him consideration with four others for the National League's final roster spot in the 2011 All-Star Game. Morse was named to Sports Illustrated'''s "All-Underrated Team". Morse finished the 2011 season with a .303 average, 31 home runs, and 95 RBI; he was in the top 10 in the National League in all three categories. He was fourth in the league in slugging percentage (.550), behind Ryan Braun, Matt Kemp, and Prince Fielder. Morse started the 2012 season on the disabled list with a strained back muscle. He was activated on June 1, 2012 and made his season debut the next day. On September 29, 2012 playing in Busch Stadium against the St. Louis Cardinals with the bases loaded, Morse hit a line drive to right field that bounced off the top of the fence. The ball was initially called in-play and Morse was tagged out trying to take second base. The play was eventually reviewed by the umpires, who ultimately overturned the call and pronounced Morse's line drive a grand slam home run. To ensure that none of the runners passed each other on the basepath, Morse was instructed to round the bases clockwise back toward the batter's box at home plate, take a mock swing at a nonexistent pitch, and then run counter-clockwise around the bases, like a usual home run. After the season, he was awarded with the GIBBY Award for Oddity of the Year. The chorus of Morse's at-bat song -- Take On Me by A-ha—notably became a