De Los Santos (0-1) allowed four runs on seven hits with three walks and two strikeouts across four innings while taking a loss against the Marlins on Sunday.
Receiving his first opportunity to start, De Los Santos didn't really improve his chances of staying with the big club. He came into the afternoon with an ERA above 6.00 from four relief appearances this season, and that number only increased. De Los Santos is now 0-1 with a 7.36 ERA, 1.64 WHIP and nine strikeouts in 11 innings. With this being a spot start, he will likely return to Triple-A Lehigh Valley at the beginning of this week.