The San Francisco 49ers have ruled left tackle Joe Staley out with a knee injury, according to NBC Sports’ Michele Tafoya. Before people lose their mind about the injury, it is worth nothing that Staley is not getting medical treatment, and he is walking around putting weight on it.
The third preseason game is viewed as the dress rehearsal for the regular season. You usually see the starters go two quarters, and sometimes a third quarter. In this case though, there is no reason to risk anything with Staley. You want him ready to play left tackle when Week 1 arrives, and more than likely he is done for the preseason. The 49ers will face the Los Angeles Chargers this Thursday, and most of the starters are unlikely to play.
John Theus took over at left tackle when Staley left. The competition for the swing role is a big one between Theus, Garry Gilliam, and potentially Zane Beadles.