The Nationals have placed RHP Jordan Zimmermann on the DL with a sore elbow and called up Colin Balester from the DL to replace him according to Ed Price on Twitter .

Zimmermann was 3-5 with a 4.63 ERA in his first major league season.

The 23 year old Balester was 7-9 with a 4.35 ERA at AAA Syracuse this year in 19 games started.