Farrell (oblique) was activated from the 60-day injured list Sunday, Brandon Warne of Access Twins reports.
Farrell is back in Minnesota's bullpen after an oblique strain sidelined him since late June. The righty was an effective relief option in 13 games before getting injured, as he posted a 1.76 ERA and 17:6 K:BB in 15.1 innings. He takes the roster spot of Andrew Albers, whom the Twins optioned Sunday.