The 49ers will not have one of their best defensive players for the rest of Sunday’s matchup with the Cardinals.

San Francisco announced at the start of the second half that Nick Bosa has been downgraded to out.

Bosa was previously questionable after going down midway through the first half. He was shown on the Fox broadcast giving a thumbs down to someone in the crowd as he was heading to the sideline medical tent after the injury.

Bosa recorded a sack in each of San Francisco’s first two games this season.

While 49ers defensive end Mykel Williams suffered a wrist injury in the first half, he is back on the field in the third quarter.

San Francisco leads Arizona 6-3 early in the third period.

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