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SANTA CLARA – Nose tackle Ian Williams, who has been a big reason for the 49ers’ dominating run defense the past three weeks, did not practice Friday due to an ankle condition.
Williams is listed as questionable on the team’s official injury report for Sunday’s game against the Kansas City Chiefs. The 49ers disclosed no further information regarding Williams’ condition, but he was seen walking without any noticeable problems.
Tight end Vernon Davis and right tackle Anthony Davis did not practice this week after sustaining injuries against the Philadelphia Eagles. Both players are expected to be out, unless they improve dramatically over the weekend.
[RELATED: 49ers injury report: Davis and Davis remain out of practice]
Cornerback Tramaine Brock (turf toe) is listed as questionable, but he will not play in Sunday’s game.
[MAIOCCO: What role will Cox fill for 49ers when Brock returns?]
Williams’ availability could be a key factor in Sunday’s game against a Chiefs' running game that features Jamaal Charles and Knile Davis.
The 49ers have allowed 152 rushing yards over the past three games against Chicago, Arizona and Philadelphia. The 49ers have not given up fewer yards rushing in a three-game stretch since the 1997 season.
49ERS
Doubtful
C Marcus Martin (knee)
Questionable
CB Tramaine Brock (toe)
T Anthony Davis (knee, ankle)
TE Vernon Davis (back)
TE Vance McDonald (knee)
S Eric Reid (hamstring)
DT Ian Williams (ankle)
Probable
S Antoine Bethea (ankle)
WR Michael Crabtree (foot)
RB Frank Gore (back)
DE Tony Jerod-Eddie (shoulder)
P Andy Lee (right ankle)
DE Justin Smith (not injury related)
CHIEFS
Out
WR Donnie Avery (groin)
S Eric Berry (ankle)
Questionable
CB Marcus Cooper (knee)
Probable
RB Jamaal Charles (ankle)
LB Tamba Hali (knee)
CB Sean Smith (groin)
RB De'Anthony Thomas (hamstring)
LB Frank Zombo (hamstring)