The White Sox optioned Murphy to Triple-A Charlotte on Sunday.
Murphy made four appearances after rejoining the big-league club Sept. 9. Over 33 games with the White Sox this season, Murphy is sporting a 3-0 record, 4.81 ERA, 1.43 WHIP and 35:16 K:BB over 33.2 innings. With Huascar Brazoban (lat) returning from the 15-day IL, Murphy was the odd man out for an active roster spot.