The Phillies optioned Backhus to Triple-A Lehigh Valley on Tuesday, Todd Zolecki of MLB.com reports.
He's clearing out to make room on the active roster for Orion Kerkering (hamstring), who is returning from a stint on the 15-day injured list. Backhus has yielded three runs with a 4:1 K:BB over three innings out of the Phillies' bullpen this season.