First pitch at Fenway Park was originally scheduled for 7:10 p.m. ET, but with the delay, a targeted time has been set for 7:40 p.m. ET.
Once the game does get underway, the Blue Jays will send Trent Thornton to the mound, with Garrett Richards toeing the rubber for the Red Sox.
Boston (12-6) earned a 4-2 victory in Tuesday's series opener to continue its hot start to the 2021 season. Toronto fell to 7-10 with the loss.