Garcia signed a minor-league contact with the Nationals on Dec. 13.
The Athletics released Garcia on Friday.
Garcia cleared waivers and was outrighted to Triple-A Las Vegas by the Athletics on Wednesday.
The Athletics designated Garcia for assignment Monday.
The Athletics optioned Garcia to Triple-A Las Vegas on Sunday.
Garcia isn't starting Tuesday against the Angels.
Garcia isn't starting Saturday against the Mariners.
Garcia is out of the lineup for Wednesday's game against the Angels.
Garcia went 1-for-3 with a solo home run in a loss to the Mets on Friday.
Garcia isn't in the lineup Thursday against Seattle.