Santiago's contract was selected as expected ahead of his scheduled start in the nightcap of Tuesday's twin bill against the Tigers.
After finishing four straight seasons with an ERA of 3.75 or below, Santiago owns a mediocre 4.84 mark over the last four years. He could be auditioning for a spot in the White Sox's rotation down the stretch, but nothing in his recent past (including his 5.84 ERA over seven starts this season for Triple-A Charlotte) suggests he'll be a particularly interesting option.