**FILE** Washington Nationals relief pitcher Ryan Mattheus (52) throws during an interleague baseball game against the Chicago White Sox at Nationals Park Thursday, April 11, 2013, in Washington. The Nationals won 7-4, sweeping the Chicago White Sox in the three game series. (AP Photo/Alex Brandon)
**FILE** Washington Nationals relief pitcher Ryan Mattheus (52) throws during an interleague baseball game against the Chicago White Sox at Nationals Park Thursday, April 11, 2013, in Washington. The Nationals won 7-4, sweeping the Chicago White Sox in the three game series. (AP Photo/Alex Brandon)
Washington Nationals relief pitcher Rafael Soriano (29) un-tucks his shirt after a baseball game against the Detroit Tigers at Nationals Park, Wednesday, May 8, 2013, in Washington. The Nationals won 3-1. (AP Photo/Alex Brandon)
Washington Nationals relief pitcher Rafael Soriano (29) un-tucks his shirt after a baseball game against the Detroit Tigers at Nationals Park, Wednesday, May 8, 2013, in Washington. The Nationals won 3-1. (AP Photo/Alex Brandon)
Washington Nationals closer Drew Storen and catcher Kurt Suzuki celebrate their win over the Los Angeles Dodgers in a baseball game in Los Angeles Monday, May 13, 2013. The Nationals won, 6-2. (AP Photo/Reed Saxon)
The Nationals beat the Dodgers 6-2 on Monday night, led by another strong start from right-hander Jordan Zimmermann. (Associated Press photo)
The Nationals beat the Dodgers 6-2 on Monday night, led by another strong start from right-hander Jordan Zimmermann. (Associated Press photo)
The Nationals celebrate after Ian Desmond hit his fifth home run of the season in the team's 7-3 victory over the Cubs. (Associated Press photo).
The Nationals celebrate after Ian Desmond hit his fifth home run of the season in the team's 7-3 victory over the Cubs. (Associated Press photo).
