BALTIMORE -- The Twins optioned left-handed reliever Tyler Robertson to Triple-A Rochester after their 6-5 win against the Orioles on Saturday. They will make a corresponding roster move before Sunday's game.
Robertson allowed one run in one inning across two appearances this season. His last outing came against the Orioles on Friday, when he gave up a go-ahead grand slam to Chris Davis in the eighth inning.
The move leaves the Twins with Brian Duensing and closer Glen Perkins as the lone left-handers in the bullpen.
Right-hander Anthony Swarzak, who is on the 15-day disabled list with two fractured ribs, is the most likely candidate to replace Robertson on the roster.