Rodriguez (shoulder) tossed a scoreless inning in his rehab debut Thursday night with Triple-A Memphis, John Denton of MLB.com reports.
Rodriguez needed just nine pitches to get through the scoreless frame and twice reached 98 mph with his four-seam fastball. Once he's deemed fully recovered from a late-spring bout of right shoulder tightness, he'll likely be an option for the Cardinals' bullpen by early next week.