Thielbar (groin) was reinstated from the 10-day injured list Wednesday, Dan Hayes of The Athletic reports.
Thielbar had been on the injured list since June 3 due to a left groin strain, but he'll return after an absence of just under two weeks. The southpaw posted a 4.29 ERA and 1.48 WHIP with five holds in 21 innings across 20 relief appearances earlier in the year, and he'll likely reclaim his setup role going forward.