The Padres optioned Gillaspie to Triple-A El Paso on Sunday.
The right-hander was called up by San Diego on Thursday, and he'll return to the minors after giving up six earned runs in two relief appearances. Gillaspie is heading back to El Paso, where he has a 3.60 ERA, 1.32 WHIP and 31:14 K:BB across 35 innings this year.