Sanchez went on the DL on June 14 with a right lat strain. The 2010 first-round pick made five appearances for Buffalo on a rehab assignment.
Before his injury, Sanchez went 5-4 with a 3.55 ERA in 11 starts for the Blue Jays.
Delabar is 2-0 with a 3.33 ERA in 27 appearances for the Jays this year.
Toronto was in Seattle on Saturday for the middle game of a three-game series.