SANTA CLARA -– Running back Reggie Bush’s availability for Sunday appears to be in doubt after not taking part in 49ers practice Thursday due to a calf strain.
The 49ers play the Arizona Cardinals on Sunday in the first division game for both teams.
Bush sustained the injury in the 49ers’ season opener on Monday, Sept. 14, against the Minnesota Vikings. He did not make the trip to Pittsburgh last week for the 49ers’ second game of the season.
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Linebacker NaVorro Bowman returned to full practice after being held out Wednesday for a scheduled rest day.