Romero was transferred to the 60-day injured list Tuesday and will undergo Tommy John surgery, Todd Zolecki of MLB.com reports.
Romero struggled to a 7.00 ERA and 1.78 WHIP in nine innings of work before hitting the injured list in early May with what was originally referred to as a left elbow sprain. As it turns out, the injury is a very serious one, and he'll now miss not only the remainder of the season but likely the majority of next year as well.