Is the 49ers Run Defense an Issue?

Maybe this is no big deal, considering teams hardly run the ball against the 49ers.

But the Niners run defense is not good. It's allowing 4.3 yards per carry, which ranks 19th out of 32 teams. That's below average. And yet, teams have run the ball only 20.9 times per game against the 49ers -- fewest in the NFL -- because the 49ers almost always have a big lead and opponents have to pass to catch up.

This past Sunday, the Cardinals committed to running the ball against San Francisco, probably because that's all they can do. They have no good wide receivers and a quarterback who can't see over the linemen when he's in the pocket. So they ran the ball 30 times and gained a whopping 234 yards and two touchdowns on the ground.

Now, the 49ers have to prepare to face the Ravens, who average 5.0 yards per carry this season -- second-best in the NFL behind Miami. They're similar to the Cardinals, considering both teams have big, strong offensive lines and quarterbacks who are extremely fast and elusive. The Ravens are just better, considering they're 11-3 and the Cardinals are 3-11.

If the 49ers offense continues to score 30 to 40 points per game, their run defense won't be an issue. But they might not score 30 points against the Ravens. Baltimore has allowed just 16.1 points per game this season -- fewest in the NFL.

If it's a tight, low-scoring game and the 49ers can't stop the run, they could lose. Of course, getting Arik Armstead and Javon Hargrave back will help the 49ers run defense, but Nick Bosa constantly rushing past the quarterback and opening up scramble lanes only will hurt the defense. He needs to be more disciplined next week than he was against Arizona.