Mayza was optioned to Triple-A Buffalo on Saturday, Arash Madani of Sportsnet.ca reports.
In a somewhat surprising move, the Blue Jays sent Mayza right back down to Buffalo after recalling the southpaw less than a week ago. Following his loss during Friday's series opener against the Cubs -- allowing two runs off three hits and a walk in 1.1 innings -- Manager John Gibbons defended his young pitcher, saying, "I think he's throwing the ball great," and that "this is his chance." It appears as though Mayza will only spend a brief time with Buffalo before coming back to the big-league club by the time rosters expand in two weeks.