Triple-A Lehigh Valley placed Holman on its 7-day injured list May 30 due to an unspecified injury.
After claiming Holman off waivers from the Tigers on May 7, the Phillies optioned him to Triple-A. Before landing on the shelf, he made five relief appearances for Lehigh Valley and turned in a 7.11 ERA, 1.97 WHIP and 12:3 K:BB in 6.1 innings.