The Padres optioned Vasquez to Triple-A El Paso on Sunday.
The right-hander was tagged for nine runs Saturday against the Rays and won't retain his spot on the big-league roster. Vasquez has a 5.18 ERA, 1.59 WHIP and 58:28 K:BB across 92 innings this season, and it's unclear if he'll receive another look in the rotation for San Diego this season, as Yu Darvish (elbow) is nearing a return from the injured list.