SANTA CLARA, Calif. (AP) - The NFL's No. 1 rushing defense enters the final quarter of the season with a few significant streaks that have been key this year to the San Francisco 49ers' success.
They are streaks that are becoming more meaningful each week for the team's defense, which hasn't allowed a 100-yard rusher in 34 consecutive games or a rushing touchdown in the last 13 games.
"Those two have been very big for us in our success, especially from a defensive standpoint," coach Jim Harbaugh said Friday. "It means quite a bit to our defense and they take pride in it. Our guys are aware of them and understand in terms of situational football what those standards can do to help your football team."
The 49ers last week became the first NFL team since 1970 to begin a season with 12 consecutive games of not allowing a rushing touchdown. To keep that streak alive this week against the Arizona Cardinals, San Francisco might have to do it without its best defensive player.
Four-time Pro Bowl linebacker Patrick Willis suffered a hamstring injury in last week's 26-0 shutout of the St. Louis Rams. Willis missed practice for the third straight day Friday and is listed as questionable to play Sunday at Arizona.
But the 49ers barely missed a beat after Willis, the NFL's leading tackler in 2007 and 2009, went down on San Francisco's fifth defensive play against the Rams. Defensive coordinator Vic Fangio said the Niners didn't change a thing defensively after they plugged in backup Larry Grant to take Willis' place.
Grant, a special teams standout who had played only a few defensive snaps in San Francisco's first 11 games, tied NaVorro Bowman with a team-high six tackles. Grant had two tackles behind the line of scrimmage and also recorded one of the 49ers' four sacks as San Francisco (10-2) clinched its first NFC West title and playoff berth since 2002.
"Everybody wants to hold up their end. That's what everybody does in this defense," said outside linebacker Parys Haralson.
The 49ers had one of their top defensive performances of the season last week, allowing a season-low 157 yards while recording their first shutout since 2009.
The Rams finished with just 31 yards rushing on 23 carries. It was the fewest yards allowed on the ground in a game this year by the 49ers, who did not allow the Rams a first down rushing.
The 13-game streak of not allowing a rushing touchdown is a franchise record and the second-longest in the NFL since 1970. The 49ers are four games away from becoming the first team in NFL history to not allow a rushing touchdown in a season.
The record for fewest rushing touchdowns allowed in a 16-game season is four, and the streaks are something that's gaining attention in the San Francisco locker room.
"It matters a lot, because it shows that each guy is on the same page, it shows that we're playing together as a defensive unit," Haralson said. "The thing about it is, most of us don't even know about the streaks. What we really focus on is winning the game. And that comes from guys hankering down knowing that we've got to be prepared to stop any team that gets in our red zone."
The 49ers have been pretty good at doing that, too. They lead the NFL in scoring defense, allowing just 13.4 points per game.
"We want to be the best defense in the NFL," said outside linebacker Ahmad Brooks, who starts opposite Haralson. "As long as we keep running backs out of the end zone and keep running backs under 100 yards, that means a lot and says we have a pretty good defense. When you've got streaks like that going on, you just want to continue to progress and keep it going."