"If all goes well, which we anticipate it going well, then he will be pitching on Saturday," Bochy said.
Cain exited his May 21 outing against Colorado after three innings with the injury.
Cain would face St. Louis's Michael Wacha on Saturday.
Chris Haft is a reporter for MLB.com. Read his blog, Haft-Baked Ideas, and follow him on Twitter at @sfgiantsbeat. Ryan Hood is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.