Jenkins often gets overlooked within the organization but has posted some very quality innings over the past couple of years. In 2013, he had a 2.70 ERA while striking out 15 batters over the course of 33 1/3 innings.
Jenkins, 26, has the ability to throw multiple innings and also could be used in a set-up role when Steve Delabar needs a day off. He had yet to pitch in the Minor Leagues this year.
To make room on the 25-man roster, right-hander Jeremy Jeffress was designated for assignment. Jeffress has caught the eye of scouts because of his ability to throw upper-90s velocity, but a lack of command has been his main issue.
Jeffress allowed four runs in 3 1/3 innings with the Blue Jays this season. He was out of options on his contract and could not be sent to the Minors without first clearing waivers.
Gregor Chisholm is a reporter for MLB.com. Read his blog, North of the Border, and follow him on Twitter @gregorMLB. This story was not subject to the approval of Major League Baseball or its clubs.