The Washington Nationals placed left-handed pitcher Ross Detwiler on the 15-Day Disabled List, retroactive to May 16, with a right back muscle strain and recalled left-handed pitcher Xavier Cedeno from Syracuse of the Triple-A International League. Nationals Executive Vice President of Baseball Operations and General Manager Mike Rizzo made the announcement.

Cedeno -- selected off waivers on April 23, after posting an 11.37 ERA in five relief appearances in '13 with Houston -- went 1-0 with a 1.74 ERA in 10 relief appearances this season with Syracuse. He posted 14 strikeouts and just three walks in 10.1 innings with the Chiefs.

In 44 relief appearances last season with the Astros, Cedeno went 0-1 with one save, six holds and a 3.77 ERA, while posting a .213 (13-for-61) BAA facing left-handed batters. The 26-year-old is 0-1 with one save, six holds and a 6.00 ERA in 52 career relief appearances during three seasons (2011-13) with Houston. 

Detwiler, 27, is 2-4 with a 2.76 ERA in eight starts this season with Washington.