Acton (shoulder) resumed throwing off a mound last week, MLB.com reports.
While the activity marks a step forward for Acton as he recovers from a right shoulder strain, Twins general manager Jeremy Zoll said Friday that the 28-year-old still has "a long road ahead of him" before returning from the 60-day injured list. Acton made four relief appearances for Minnesota and surrendered five runs (two earned) on four hits and three walks while striking out nine batters over 6.2 innings before landing on the IL in late April.