Atlanta selected Murphy's contract from Triple-A Gwinnett on Monday.
The 22-year-old Murphy has made 16 starts this season between Double-A Columbus and Gwinnett, registering a 4.44 ERA, 1.26 WHIP and 92:38 K:BB over 81 innings. Murphy has never made a relief appearance in professional ball, but Atlanta is expected to deploy him as a long man out of the bullpen to begin his time in the majors, per Mark Bowman of MLB.com.