Tolleson had been out since May 26 with a strained groin and recently completed a rehab assignment with Triple-A Buffalo. He was out of options and the lack of space on the 25-man roster resulted in the latest roster move.
This marks the second time this season Tolleson was designated for assignment. He began the year in Toronto, but was designated for assignment April 24 and eventually joined Buffalo after clearing waivers.
The Blue Jays have a set infield with Jose Reyes and Devon Travis up the middle and Ryan Goins as the primary backup. Toronto also has infielder Munenori Kawasaki on the 40-man roster and there wasn't a clear path for Tolleson to return.
The hope for Toronto is that Tolleson once again will clear waivers as the club attempts to hold onto its depth. The 31-year-old has the ability to play the infield and outfield, and he hit .268 (11-for-41) with six extra-base hits and three RBIs in 19 games.