Noting that Posey's condition had continued to improve, manager Bruce Bochy said that Monday's scheduled off-day will "give us some time to see how he comes out of [Sunday]."
Posey's return was timely, since the Giants lost their biggest bat when Michael Morse had to be scratched with a sore left foot.
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.