The Phillies optioned Johnson to Triple-A Lehigh Valley on Wednesday.
The 27-year-old righty will be pushed back to Triple-A to make room for Brad Keller's (forearm) return from the injured list. Johnson made eight appearances with the Phillies after being called up June 18, and he surrendered six earned runs and posted a 10:7 K:BB in 7.2 innings while up in the majors. Although he carries a 7.15 ERA in the big leagues, he remains an option to return to Philadelphia later in the year if its bullpen depth is tested.