The Twins placed Coulombe on the 15-day injured list Sunday due to an extensor strain in his left forearm.
It's unclear when Coulombe sustained the injury since he hasn't pitched since Wednesday. The left-hander hasn't given up a run through 19 appearances this season and owns a stellar 19:2 K:BB over 16.2 innings out of the Minnesota bullpen, but he'll now be unavailable for at least the next couple weeks.