McAllister will get the start today that belonged to Trevor Bauer. They also called up Shawn Morimando and designated Michael Martinez for assignment.
Morimando was on the 40 man roster meaning they had already used his option for this year when they sent him down to the minors after spring training.
My guess is today that they try to get 3 innings out of McAllister. Not sure if they plan to do a bullpen day or if they plan to let Morimando pitch after Toronto has stacked its lineup with left handed hitters to face the righty McAllister. Morimando may just be there if they need a bunch of mopup innings if we get too far behind. If it was me I would try for McAllister for 3, Morimando for 4 and then find two innings out of the rest of the bullpen...assuming we don't go 19 again today!