Denver, CO -- (Sports Network) - The Colorado Rockies placed first baseman Todd Helton on the 15-day disabled list Friday with a strained lower back. The move is retroactive to July 3.

Helton, 34, is hitting .266 with seven home runs and 29 runs batted in through 81 games this season. He last played on Wednesday against San Diego, going 0- for-2 with a pair of walks in Colorado's 8-1 win.

A five-time National League All-Star, Helton is a career .328 hitter with 310 home runs and 1,116 RBI in 1,659 games over 12 seasons, all with the Rockies. Prior to this season, Helton had hit at least .300 in every season since hitting .280 in 35 games in his rookie season of 1997.

To take Helton's place, the Rockies recalled infielder Joe Koshansky from Triple-A Colorado Springs. The 26-year-old Koshansky is hitting .281 with 18 homers and 78 RBI at Triple-A, and was 1-for-12 as a September call-up with the Rockies last season.