Castro (shoulder) has slashed .245/.327/.327 with one home run in 13 games since being reinstated from Triple-A Lehigh Valley's 60-day injured list July 23.
Castro had been on the shelf since April 3 due to the left shoulder injury before he was cleared to rejoin Lehigh Valley after completing a three-game rehab assignment shortly after the All-Star break. The 25-year-old infielder retains a spot on the Phillies' 40-man roster, but he hasn't appeared in the majors all season, and a promotion to Philadelphia wouldn't seem to be imminent.