The move makes room on the 26-man roster for Jonathan Ornelas, whose contract was selected by the Athletics from Las Vegas. Thomas has been on the big-league roster since late April, but in 16 games since July 1 he's gone 4-for-34 (.118) with one RBI and a 38.9 percent strikeout rate while operating in a reserve role. He'll head back to Triple-A, where he's slashing .309/.397/.574 with one steal, five home runs and 19 RBI over 78 plate appearances this season.

Thomas suffered an injury scare Monday after being struck in the left wrist by a pitch. He was fortunate to avoid any structural damage, but he dealt with a painful bruise that kept him on the bench for the ensuing four contests. Thomas is back in the starting nine Sunday against Twins southpaw Connor Prielipp and should continue to hold down the short side of a platoon in the Athletics outfield.