Castillo (2-2) was the winning pitcher after firing a scoreless inning with a strikeout against the Reds on Thursday.
Starter Eric Lauer was only deployed for four innings, so the official scorer deemed Castillo's scoreless appearance worthy of the victory. Kirby Yates and Craig Stammen are firmly entrenched as the Padres' top late-inning options, but Castillo is making a strong case for a larger role next year after posting a 2.67 ERA, 0.86 WHIP and 11.6 K.9 over 30.1 innings.