Hunter and Williams were hurt on the second-to-last play of the third quarter of Sunday's 31-21 win, on which Hunter ran for a 2-yard gain. The players were helped off the field and then carted to the locker room. Harbaugh said Monday that Williams was injured before contact when his foot planted into the turf.
The 24-year-old Williams — a third-year pro who had two costly fumbles in a 20-17 overtime loss to the Giants in last season's NFC championship game — had 14 catches for 212 yards and a touchdown this year.
Now, James will probably get his first true look on the field. The rookie out of Oregon rushed out of the locker room to a meeting before addressing reporters.
"I expect dynamic plays, man," Dixon said. "I watch him every day on the practice field, and he's making plays, going up to get the ball. They have him doing Percy Harvin stuff when we're playing teams like that, and he really is a great talent. I feel like he's going to come in and make plays. I know he's hungry."
San Francisco activated running back Jewel Hampton from the non-football injury list and added him to the 53-man roster. They still have one open spot on the active roster and worked out kickers on Tuesday morning.
"Dave's our guy," punter Andy Lee said of kicker David Akers.
The 49ers also released safety Eddie Whitley from the practice squad and signed wideout and returner Chad Hall to the practice squad.
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