The Reds reinstated Gibaut (forearm) from the 60-day injured list Tuesday.
The right-hander hasn't seen a big-league mound this season while coming back from forearm surgery, but he'll join the Reds for the final week of the campaign. Gibaut allowed five earned runs over 3.2 frames in four rehab outings with Triple-A Louisville and should fill a low-leverage relief role.