Middleton (forearm) could throw a bullpen session later this week, Derrick Goold of the St. Louis Post-Dispatch reports.
Middleton recently did some long-tossing without issue and is almost ready to throw from a mound for the first time since going down with a right forearm strain in mid-March. Because he's missed so much time, the veteran reliever would figure to need multiple rehab appearances, once he's cleared for game action.