Cheng underwent labrum surgery during the off-season and has been pitching on the side most of the season in an effort to work himself back. After spending five months in extended spring training, Cheng will begin a rehab assignment this week with Auburn.
With just three weeks left in the season the Blue Jays could have held off on this, but wanted to put Cheng into some real action with his clean bill of health so they can gauge an off-season workout program more effectively.
Cheng is expected to pitch out of the bullpen for the rest of the season, gradually increasing his pitch count with each appearance.
The southpaw went 11-5 with a 2.70 ERA in 143 1/3 innings last year for Low-A Lansing.