Leone was recalled from Triple-A Buffalo on Sunday, Shi Davidi of Sportsnet reports.
Leone will help give the Blue Jays some extra depth in the bullpen after J.P. Howell (shoulder) landed on the 10-day disabled list in a corresponding move. Howell had been assuming higher-leverage duty in relief, but Leone figures to be ticketed for mostly mop-up work until he gains the trust of manager John Gibbons.