Wacha (shoulder) is scheduled to throw a bullpen session Saturday, Jen McCaffrey of The Athletic reports.
Wacha landed on the 15-day injured list last week with shoulder inflammation, so his quick return to mound work is an encouraging sign. The veteran right-hander will be eligible to be reinstated shortly after the All-Star break, and it's possible he's able to do so without the need for a minor-league rehab assignment.