The Blue Jays recalled Thornton from Triple-A Buffalo on Sunday.
Thornton will fortify the Toronto bullpen after the Blue Jays placed left-hander Tim Mayza (shoulder) on the 15-day injured list in a corresponding move. Over his 27 relief appearances with the big club this season spanning 38 innings, Thornton has compiled a 4.26 ERA, 1.29 WHIP and 30:15 K:BB.