The Reds announced that Votto was placed on the 15-day disabled list because of a distal squad strain in his left knee, and Bruce was activated after recovering from arthroscopic surgery on his left knee.
Votto hasn't played since being in both ends of a doubleheader on May 15, and his transaction was backdated to the 16th. Cincinnati's first baseman is batting .257 with six home runs and a .410 on-base percentage this season, but he was hitting just .209 (9-for-43) in 12 games in May.
Bruce, meanwhile, batted .216 with a .352 on-base percentage in his first 30 games of the season. The right fielder last played for the Reds on May 4, and veteran reserve Chris Heisey saw a lot of playing time in his absence.
Spencer Fordin is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.