Castano (pectoral) is expected to begin a throwing program next week, MLB.com reports.
Castano will need more than a week to build up as he works his way back from a right pectoral strain, so he doesn't appear to be in line to return from the 15-day injured list until after the All-Star break. Before landing on the shelf June 21, Castano turned in a 3.92 ERA, 1.35 WHIP and 17:6 K:BB in 20.2 innings over 10 appearances out of the Colorado bullpen.