The Angels made the move Wednesday.
The 33-year-old Blanton struggled in spring training with a 7.08 ERA in five appearances over 20 1/3 innings. He was 2-14 last year and sent to the bullpen in midseason.
The Angels will absorb Blanton's contract and pay him $7.5 million this year, with another $1 million to buy out the $8 million club option for 2015.
Blanton's departure leaves the Angels with 39 players on their 40-man roster and takes him out of competition for a bullpen roster spot. The team's rotation appears set with Jered Weaver, C.J. Wilson, Garrett Richards, Hector Santiago and Tyler Skaggs.