Sewald (oblique) is scheduled to throw a bullpen session Saturday, Theo Mackie of The Arizona Republic reports.
Saturday's bullpen session will mark Sewald's first opportunity to throw off a mound since he suffered a Grade 2 left oblique strain in late March. He will likely require additional bullpen sessions before progressing to facing live hitters and potentially a rehab assignment in the minors, but the right-hander seems to be trending toward a return in late April. Until then, Kevin Ginkel will continue serving as Arizona's closer.