Santillan struggled in Thursday's loss to the Padres, retiring two batters while hitting two batters, walking another and then giving up a bases-loaded double. A lack of command of his slider was the main culprit for his issues, Mark Sheldon of MLB.com reports. "Right from pitch one, it looked like he was maybe overthrowing his slider a little bit, pulling it," Reds manager David Bell said.
Since nailing down the save on Opening Day, Santillan has declined, picking up one hold over the weekend, but seeing his ERA skyrocket to 8.10 with a WHIP of 1.50. Lucas Sims is now back from the injured list, and Santillan has been pushed down in the closer pecking order as a result.