Tight end Vernon Davis was back on the practice field today and taking part in non-contact work. Davis suffered a concussion in the first quarter of Sunday's loss when he he absorbed a jarring hit by Seahawks safety Kam Chancellor.
Davis has passed two stages of the NFL's post-concussion protocol - being cleared by an independent neurologist and passing the so-called exertion test in which he is asymptomatic after vigorous exercise. Davis would have to go through today's session and then pass a contact test before he receives full clearance to play Sunday against Arizona.
If he doesn't, Delanie Walker and undrafted rookie Garrett Celek would step in as his replacements. Walker would take over Davis' role in single-tight end formations; Celek would fill Davis' role when there are two tight ends on the field.
Tarell Brown (shoulder, knee), Aldon Smith (shoulder), Ahmad Brooks (shoulder), Will Tukuafu (neck), Tavares Gooden (ribs) and Bruce Miller (shoulder) were, like Davis, wearing black no-contact jerseys. Outside linebacker Clark Haggans, who missed Sunday's game with a shoulder injury, was not in a black jersey.
Center Jonathan Goodwin was under the weather and was not taking part in the beginning of Thursday's session.
Justin Smith was seen coming off the field from the morning walk-through but did not attend the beginning of Thursday's afternoon practice.
- Matt Barrows