Dobnak's contract was selected from Triple-A St. Paul on Sunday.
He will take Diego Castillo's 40-man roster spot on the final day of the season after being designated for assignment less than two weeks ago. Dobnak may not hold his 40-man roster spot all offseason, as he logged a 5.87 ERA and 1.83 WHIP in 7.2 innings in the majors this season and will turn 30 in January. Dobnak had a 4.25 ERA, 1.45 WHIP and 134 strikeouts in 133.1 innings at Triple-A this season.