The Brewers reinstated Harrison (forearm) from the 15-day injured list ahead of his scheduled start Wednesday versus the Pirates in Milwaukee.
The 24-year-old lefty will make his return to the Milwaukee rotation after missing just under four weeks while recovering from left forearm extensor tendinopathy. Harrison covered 5.2 innings and 68 pitches during his lone rehab start at High-A Wisconsin last Thursday, so he should be capable of handling something close to a normal workload as he takes the hill for the Brewers for the first time since July 8.