OAKLAND -- The A's have released right-handed pitcher Santiago Casilla.
 
Casilla was designated for assignment last Saturday after compiling a 3.16 ERA in 26 games with Oakland. He had a .170 opponents batting average but walked 20 batters in 31 1/3 innings.
The 37-year-old right-hander made his Major League debut with the A's in 2004 and spent six seasons with Oakland before pitching for San Francisco from 2010-16. He spent the last two seasons with the A's and went 10-9 with 21 saves and a 4.67 ERA in 241 career appearances with Oakland. Casilla is 42-31 with 144 saves and a 3.29 ERA in 655 career relief appearances over 15 seasons in the Majors.