"We were being cautious," said Giants manager Bruce Bochy, who added Pence was scheduled to be checked by doctors.
Pence departed after singling in the third inning. He also was hit by a pitch on his right leg in the first inning, which, as Giants general manager Bobby Evans indicated, prompted his early exit.
"Just didn't want to push him after he was HBP," Evans said in a text. "Maybe felt scar tissue if anything during three innings he played. Felt good after he came out."
Based on the Giants' preliminary plans, Pence was expected to play five innings Sunday for Sacramento at Round Rock, then rest Monday before resuming his playing regimen Tuesday at New Orleans.
Chris Haft has covered the Giants since 2005, and for MLB.com since 2007. Follow him on Twitter at @sfgiantsbeat and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.