The Pirates announced Polanco had been placed on the DL retroactive to May 15 and called up Danny Ortiz from Triple-A to take his spot on the roster.
Polanco was removed in the fifth inning of Sunday's game against the Arizona Diamondbacks after pulling up lame trying to run out a ground ball.
The 25-year-old has been a consistent contributor for the Pirates since making his debut during the 2014 season.
After showcasing his speed and hitting ability in his first couple of seasons, Polanco added power to his repertoire in 2016. The outfielder finished with 22 home runs, more than double what he produced the year before and second on the team behind only Andrew McCutchen.
So far this season he is hitting .252/.336/.370 with 12 extra-base hits and six stolen bases.
Regardless of where he is lining up in the field, though, Polanco has become a middle-of-the-order presence who will leave a significant hole if he is forced to miss time. Adam Frazier and John Jaso are both capable of playing the corner outfield, although the team will look toward its veterans to pick up the slack in the lineup.