The Mariners made the move Monday.
The 24-year-old Montero was recalled from his rehabilitation assignment Friday following a verbal altercation with a Mariners scout at a Class A Northwest League game.
General manager Jack Zduriencik said Friday that Montero wouldn't play again this year following the heated argument in the stands in Boise, Idaho. Zduriencik said the actions of Montero and cross-checker Butch Baccala were ''unacceptable'' and ''embarrassing'' for the club.
Montero has been asked to focus on off-field issues. He was trying to come back from an oblique injury in time to join Seattle in September. Montero, a former Yankees prospect, batted .235 with two RBIs in six games during his third season with Seattle.