Alaniz was recalled by the Reds to serve as the 29th man in Wednesday's doubleheader against the Cardinals.
Alaniz missed just over three weeks due to a strained left calf earlier in the season, and he was sent down after he was reinstated from the injured list in mid-August. He's allowed one run on a hit and three walks while striking out three in 2.2 innings across three major-league appearances this year and will provide a fresh bullpen arm for Wednesday's twin bill.