Casilla could be activated without another rehab appearance, but Bochy said Casilla would "more than likely" return to San Jose for one more appearance Saturday. The expectation is that Casilla will be available for the team's series next week against the White Sox.
Casilla owns a 1.37 ERA through 26 1/3 IP. He strained his right hamstring on May 21.
First baseman Brandon Belt once again took ground balls before Friday night's game, and began taking two-handed swings, instead of just the one-handed ones he's taken the last couple days. He continues to progress in his recovery from a broken left thumb.
Belt is hitting .264 with nine home runs and 18 RBIs in 35 games this season.
Ryan Hood is an associate reporter for MLB.com. Follow him on Twitter @ryanhood19. This story was not subject to the approval of Major League Baseball or its clubs.