Alex Smith injury: Timeline for 49ers QB to return to action

After being knocked out of the San Francisco 49ers' 24-24 tie with the St. Louis Rams on Sunday, quarterback Alex Smith will have to go through the NFL's extensive concussion protocol before being cleared to play. That includes being cleared at rest and after exertion, as well as being cleared by two separate neurologists.

San Francisco offensive tackle Joe Staley returned from a concussion in just a week, but every player recovers at a unique pace. This is Smith's second concussion in two years, with the other coming in a loss to Dallas in Week 2 of the 2011 season.

Smith suffered the concussion on a quarterback sneak and tried to continue playing despite having blurred vision, but the eight-year veteran had to be replaced by Colin Kaepernick after getting hit by Jo-Lonn Dunbar.

The 49ers' next game is Nov. 19 against the Chicago Bears, and while the practice timeline being pushed back by one day buys Smith some extra time, it is unlikely that the team will know the fate of their signal caller until Wednesday or Thursday at the earliest.

This story was originally published on SBNation.com.