But more critical than Boldin’s five-catch performance which resulted in 90 yards and a touchdown on seven targets was the show by Frank Gore. The veteran rusher totaled 153 yards and a touchdown on 20 carries for the 49ers.
It was his best performance of the season. Gore consistently gashed the Rams defensive front—he gained at least 13 yards on four different carries—for a 7.7 yards-per-carry average. A thinly spread St. Louis defense was ill-equipped to contain him with Jo-Lonn Dunbar suspended and Alec Ogletree learning on the job.
It has to close the running lanes.
What's more, when Gore wasn't rumbling toward the end zone, Boldin was out there dismantling Cortland Finnegan and Janoris Jenkins. Now, Michael Crabtree is returning to be Boldin's running mate, St. Louis is without Finnegan for the rest of the year and Trumaine Johnson's status is in question.
That can only mean one thing: more soft zone coverage.
After Johnson left in Week 12, the Rams turned to more zones while nursing a big lead against the Chicago Bears. That's pretty much the only time when primarily running soft zones is OK—if the opposition is going to score, at least make it take a while—but a lack of cornerback depth will likely force their hand in that direction again on Sunday.
Chicago ended up scoring seven questionable second-half points; St. Louis put 15 up in the fourth quarter.
Playing zone also allows more eyes to be on Colin Kaepernick as a rusher, but expect the Rams to diversify their coverage even if they stay away from man-to-man. Boldin would feast on predictable zones with comeback routes all day. St. Louis has to counter those with undercutting linebackers and slot corners; perhaps Ogletree can bait Kaepernick into throwing a pick.
The first matchup between St. Louis and San Francisco took place before St. Louis' running game took off. Zac Stacy had yet to emerge, Daryl Richardson was hurt and Benny Cunningham had never seen more than five touches in a game.
Stacy and guard Chris Williams are also questionable for Week 13, while Richardson was inactive for Week 12. Even if they all miss the upcoming contest (unlikely; at least one of the running backs will probably go), St. Louis still needs to challenge the 49ers defensive front.
San Francisco is doing better against the run, averaging 3.9 yards per carry. However, the first time that the two NFC West squads met was the first and only time through six weeks that San Francisco hadn't allowed at least 131 rushing yards or a touchdown to its opposition's running backs.
With a combined 181 rushing yards and a touchdown on 20 carries in his last two games, Cunningham is now averaging six yards per carry this season. Stacy is putting up 4.4, and Richardson averaged 4.9 against the Seattle Seahawks in his last game (Week 8).
San Francisco has surrendered four-plus yards per carry in each of its last two games.
Cashing points in through the air will prove to be difficult for Kellen Clemens; opposing tight ends haven't topped 75 yards in a game as a position group, totaled four touchdowns this season and were shut out by the 49ers in Week 12.
Wideouts haven't scored on them since before San Francisco's bye.
The smaller No. 11 likes to do that.
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