Bush (shoulder) was activated from the 15-day injured list Friday, Todd Rosiak of the Milwaukee Journal Sentinel reports.
The 37-year-old had been shelved for nearly two months with right shoulder tendinitis but will now return to the Brewers' bullpen, forcing Trevor Megill back to Triple-A Nashville. Bush made six appearances during his rehab assignment, throwing five innings while giving up one unearned run and striking out six batters.