The move is retroactive to Saturday, when he injured himself during an indoor workout. With ace lefty Madison Bumgarner sidelined by a broken pinkie finger in his pitching hand, this marks the second straight season the Giants' top two in the rotation are on the DL.
Cueto (1-0) had already been pushed back from a scheduled start Tuesday night against the Arizona Diamondbacks, and Andrew Suarez is set to start the series finale Wednesday afternoon.
Manager Bruce Bochy said Cueto threw a bullpen Tuesday prior to going through a series of tests with the training staff before the club decided on the DL.
San Francisco recalled lefty Steven Okert from Triple-A Sacramento, and he was available.