Cain scratched from next start with sore hamstring
Cain left his previous start against Colorado last Wednesday when he felt a twinge in his hamstring on the last pitch of the third inning.
Cain tested the hamstring out in a bullpen session Saturday, but manager Bruce Bochy said after the game that Cain will not start make his scheduled start on Monday against the Chicago Cubs.
Yusmeiro Petit will start in Cain's place.
Cain is 1-3 with a 3.66 ERA in eight starts this season.