Chargers defense vs. Forsett, Ravens

The Chargers will learn a lot about their defense’s toughness Sunday.

The Ravens love to stretch and pound with their zone-based ground game. Running back Justin Forsett gains 5.8 yards per carry, second-best in the NFL.

Former Super Bowl MVP Joe Flacco’s play-action passes to speedsters Torrey Smith and Steve Smith argue against overplaying the run, and the guard tandem of Marshal Yanda and Kelechi Osemele is among the NFL’s best. A pro-Ravens crowd’s quiet will assist Ravens’ communications.

“It’s gonna be the type of game you have to win if you want to go to the playoffs,” Chargers linebacker and ex-Raven Jarret Johnson said.

Baltimore’s Gary Kubiak-designed offense is similar to the Texans’ offense the Chargers faced in the 2013 opener when Kubiak was Houston’s head coach.

“Everything is centered around the run,” Johnson said.

Linebacker Melvin Ingram has aided San Diego’s run defense since his return two games ago from a hip injury. Crashing down the line on third-and-1, he blasted the Raiders’ Darren McFadden for no gain.

Flacco said Baltimore’s guards “bring a lot of physicality” and “can be intimidating guys.”

Winning with guile as much as power is a Chargers strength. Defensive coordinator John Pagano has expanded Eric Weddle’s playcalling role since the Week 10 bye. The move coincided with fewer snaps for linebacker Donald Butler, whose role could expand with Andrew Gachkar (knee) doubtful.

Ravens coach John Harbaugh likened Weddle to the Steelers’ Troy Polamalu, an unpredictable eight-time Pro Bowler and longtime Ravens rival.

Flacco said Weddle is the straw that stirs Pagano’s varied schemes.

“With Weddle back there,” he said, “they can disguise what they are doing very well, because he is good at doing it, and he knows what he is doing, and he knows how to get where he needs to be.

“The fact that he’s the kind of player that he is allows them to disguise some things and hold things for a longer period of time than maybe some other teams.”