The Athletics outrighted Zhuang to Triple-A Las Vegas on Tuesday.
Zhuang is no longer a member of the Athletics' 40-man roster after the Athletics designated him for assignment Friday, but he'll remain in the organization after going unclaimed off waivers. The 25-year-old righty has yet to make his MLB debut and has compiled a 6.42 ERA, 1.60 WHIP and 63:33 K:BB in 82.2 innings between stops with Las Vegas and Double-A Midland.