The Reds expected to have Bruce back by Friday. He is allowed to be away from the club for a minimum of three days to a maximum of seven days.
Bruce is batting .215/.300/.379 with 10 home runs and 42 RBIs in 87 games this season. Tuesday will mark the third time this season that Bruce and the injured Joey Votto and Brandon Phillips are all out of the lineup at the same time. It also happened on July 10 and July 21.
This is Partch's fifth callup to the Reds this season. He has only appeared in five games over those callups and allowed no runs, two hits and seven walks.
Reds manager Bryan Price opted to have another reliever called up, which gives the bullpen eight pitchers again.
"[Monday] night we had 15 innings and we've used the bullpen a lot," Price said. "We'll need coverage for probably another day or two as well after getting through yesterday."
Mark Sheldon is a reporter for MLB.com. Read his blog, Mark My Word, and follow him on Twitter @m_sheldon. This story was not subject to the approval of Major League Baseball or its clubs.