Blanton, 32, is 2-13 with a 5.66 earned-run average. No major league pitcher has given up more hits, runs or home runs.
He is under contract for $6.5 million this season and $7.5 million next season, with a $1-million buyout
guaranteed for the 2015 season.
Scioscia said there is no timetable for Blanton to return to the starting rotation and said the Angels want him to work on improvements without the pressure inherent in a rotation spot.
"We just want to get Joe out of the grind of starting," Scioscia said, "and give him a chance to make some adjustments."