Castro (shoulder) began a rehab assignment Thursday and has gone 1-for-6 with a run scored and an RBI between two games in the rookie-level Florida Complex League and Single-A Clearwater.
After failing to win a spot on the Phillies' Opening Day roster, Castro was optioned to Triple-A Lehigh Valley coming out of spring training. He appeared in just two games for Lehigh Valley before being placed on the 7-day injured list April 3 with left shoulder subscapular bursitis, per Tom Housenick of The Allentown Morning Call. Lehigh Valley later transferred Castro to its 60-day injured list, but since he's already missed more than two months with the injury, he'll be eligible for activation once he completes his rehab assignment.