KANSAS CITY (AP) — The Royals are placing left-handed starter Danny Duffy on the 10-day injured list with a left hamstring strain.

Duffy suffered the injury Monday while running sprints in the outfield before the Royals’ matchup against the Red Sox at Fenway Park. He is expected to miss 2-3 weeks of action, but he told Fox Sports Kansas City’s Joel Goldberg that he will be able to keep throwing to maintain strength in his pitching shoulder.

The 30-year-old Duffy is 5-6 with a 4.93 ERA across 18 starts in his ninth Major League season with the Royals.