The Nationals placed Ryan Zimmerman on the 15-day disabled list with a right hamstring strain, the latest blow to the veteran third baseman, who has battled injuries all season.
Zimmerman hurt himself running down the first-base line Tuesday night in Colorado, beating out a potential double play in the sixth inning of the Nationals' 7-4 win over the Rockies. He pulled up lame about three steps short of the bag, then fell to the ground and immediately motioned for a trainer before limping off the field with assistance.
The Nationals won't know a timetable for Zimmerman's return until results of Wednesday morning's MRI are read by doctors, but he'll be out at least the minimum 15 days.
Infielder Zach Walters was recalled from Class AAA to take Zimmerman's roster spot and joined the club in time for Wednesday's 3:10 p.m. EDT series finale at Coors Field. The 24-year-old was hitting .300 with 15 homers and 48 RBI in 60 games with Syracuse.
This is Zimmerman's second DL stint this season. He missed seven weeks after fracturing his right thumb in mid-April. He also has been battling a chronic shoulder condition that hampers his ability to throw.