Lincecum had informed pitching coach Dave Righetti of his illness, but word didn't spread immediately to Bochy.
"I didn't know he was sick," Bochy said.
Lincecum, 30, proved to be resilient enough that Bochy deemed him available to pitch in Tuesday's World Series opener against the Kansas City Royals.
"He was good to go for the game, and he's fine now," Bochy said.
Chris Haft is a reporter for MLB.com. Read his blog, Haft-Baked Ideas, and follow him on Twitter at @sfgiantsbeat. This story was not subject to the approval of Major League Baseball or its clubs.