Fisher (hamstring) was reinstated from the 10-day injured list Thursday.
Fisher has been sidelined since the start of the regular season due to hamstring and calf issues, but he resumed his rehab assignment with Triple-A Nashville in early June. Across 17 rehab games, he hit .220 with a home run, eight runs and six RBI. The 27-year-old is out of minor-league options, so he'll join the Brewers for now and should serve mainly in a depth role.