Should circumstances necessitate bringing aboard a fresh catcher in case injury, illness or fatigue strikes Posey or Brown, Bochy indicated that the Giants have a mystery catcher who they can summon.
"We do have one of our Minor League guys staying sharp," Bochy said.
Bochy declined to identify the possible backup. However, a likely candidate is Tony Sanchez, who spent most of the season with Toronto's Triple-A Buffalo affiliate. The Blue Jays released Sanchez on July 28, and San Francisco signed him on Aug. 3. Entering Friday, he was batting .200 (8-for-40) in 13 games with Triple-A Sacramento.
Selected fourth overall by Pittsburgh in the 2009 Draft, Sanchez batted .259 in 51 games for the Pirates over parts of the previous three seasons.
With Posey needing a break from catching, Brown started Friday against the Cubs, though he had just recovered from an illness which the Giants feared was mononucleosis. Posey was in the lineup at first base.
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.