Zimmermann (biceps) allowed just two walks over five hitless innings, striking out one and earning the win over Triple-A Memphis on Tuesday.
Zimmermann was literally unhittable in his third rehab start. He has allowed just two runs (one earned) on five hits and eight walks across 11 innings in his three rehab starts. It's possible the southpaw could be back with Baltimore as early as Sunday versus Boston if he stays on regular rest.