The Blue Jays optioned Macko to Triple-A Buffalo on Tuesday, Keegan Matheson of MLB.com reports.
The left-hander delivered two scoreless appearances early in camp but was never a likely bet to make Toronto's Opening Day roster. Macko started in 10 of his 18 appearances at Triple-A last season, finishing with a 5.06 ERA, 1.52 WHIP and 65:36 K:BB over 64 innings.