Barreto is on the Athletics' roster for Wednesday's wild-card game against the Rays, Susan Slusser of the San Francisco Chronicle reports.
Barreto was expected to secure the final bench spot with Stephen Piscotty not fully recovered from an ankle sprain. Barreto struggled to an awful .138/.263/.401 slash line in 23 games this season and is unlikely to be used as anything other than a pinch runner or defensive replacement.