The Twins announced the move on Tuesday, one day after sending outfielder Delmon Young to the Tigers for minor league left-hander Cole Nelson and a player to be named later.
That player is Oliveros, who has appeared in nine games for the Tigers this season. He made his big league debut on July 1 and went 0-0 with a 5.63 ERA but has spent most of the season in Triple-A. He has gone 1-3 with a 6.43 ERA and five saves in 22 appearances for Toledo.
Oliveros has been assigned to Triple-A Rochester.