Wacha (shoulder) threw a bullpen session Sunday and will take part in a simulated game within the next week, Justin Toscano of The Bergen Record reports.
Wacha struggled to a 6.43 ERA in three starts this season before landing on the injured list with shoulder inflammation. He was never shut down from throwing for more than a couple days, so his absence doesn't appear set to be a particularly long one, though his exact return date remains unclear.