The quarterback -- who suffered a concussion on Sunday -- practiced in a black (non-contact) jersey for a fourth consecutive day on Saturday, according to Matt Barrows of The Sacramento Bee.
Barrows wrote that Smith's Saturday practice "suggests that he's playing on Monday but doesn't quite clinch it."
Smith was knocked out of the Niners' 24-24 tie with the St. Louis Rams after taking a hit to the back of the helmet at the end of a 4-yard scramble. He completed a touchdown drive, but didn't return after telling the team he was experiencing blurred vision.
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