Drabek felt a "popping sensation" in his elbow last week during an outing against the Washington Nationals. Preliminary tests showed Drabek suffered a torn ulnar collateral ligament (UCL) and a second opinion from Dr. James Andrews confirmed the diagnosis.
The 24-year-old underwent the same procedure four years ago while a member of the Phillies' farm system and required 13 months recovery and rehab before returning to the major leagues.
In 13 starts this season, Drabek was 4-7 with a 4.67 ERA. He's one of three Toronto starters dealing with injuries this season.
"Based on the multiple evaluations, I think this was the only option," Jays manager John Farrell said prior to Monday's game against the Brewers in Milwaukee. "In some ways, because of the extent of the injury, it was pretty much taken out of his hands and the proper road and the best course of action is to have the surgery done."
Drabek is only one of Toronto's three ailing starters.
Right-hander Drew Hutchinson will get a second opinion on his ailing elbow this week by Dr. Tim Kremcheck in Cincinnati. A third starter, right-hander Brandon Morrow, is on the disabled list with a strained rib cage muscle.