The weather forecast for Green Bay on Sunday: 73 degrees, mostly sunny with a wind out of the north at 7 mph.
The mild conditions are good news for Kyle Williams, who looks like he'll be the 49ers' punt returner in the opener. For the second straight day, Ted Ginn (ankle) worked out on a side field with trainers while the 49ers began practice.
Joining Ginn was running back Brandon Jacobs (knee), whose once-pronounced limp is hardly noticeable but who also seems unlikely to play. If that's the case, rookie LaMichael James would be active for the game and would be Williams' backup on punt returns. Kendall Hunter is likely to handle kick returns.
Jacobs' absence also would mean that short-yardage duties likely would be handled by Anthony Dixon or Frank Gore.
Thursday injury report:
Did not participate in practice
WR Ted Ginn (ankle), RB Brandon Jacobs (knee)
Out (Definitely Will Not Play)
RB James Starks (toe)
Did Not Participate In Practice
LB Jamari Lattimore (ankle)
Limited Participation in Practice
TE Tom Crabtree (shoulder), LB Rob Francois (hamstring), CB Davon House (shoulder), S Sean Richardson (hamstring)
Full Participation in Practice
DT B.J. Raji (ankle)
-- Matt Barrows