Chargers face a major challenge against the Jaguars’ dominant defense

Philip Rivers has feasted on the Jacksonville Jaguars, completing 163 of 229 passes for 2,119 yards and 19 touchdowns in seven games — six of them Chargers victories — but the all-you-can-eat buffet could end Sunday.

When the Chargers (3-5) travel to EverBank Field, they will face a tenacious Jaguars defense that bears little resemblance to the units they trampled for years.

Jacksonville, now known as “Sacksonville,” leads the NFL with 35 sacks. Defensive end Calais Campbell, a former Arizona Cardinals star who signed a four-year, $60-million deal last winter, has a league-high 11 sacks, and fellow ends Yannick Ngakoue (6.5) and Dante Fowler (5.5) have combined for 12.

With 10 sacks against the Houston Texans in Week 1 and 10 against the Indianapolis Colts in Week 7, Jacksonville joined the 1984 Chicago Bears and 1967 Oakland Raiders as the only teams with 10-plus sacks in multiple games of a single season since 1940.

The Jaguars (5-3) have given up a league-low 14.6 points and 156.4 yards passing a game while holding opponents to seven points or fewer in four of eight games. They rank third with 16 takeaways and have scored a league-high 77 points off turnovers.

“This is certainly the best group of guys they’ve had together,” Rivers said before Wednesday’s practice. “They’re playing really well, with a lot of confidence, and they’re playing fast. They’re all active and relentless in the way they rush.”

The Chargers line has done a good job of protecting Rivers, who has been sacked 11 times through eight games after being taken down 36 times last season, and has neutralized some of the game’s best pass rushers, such as the Denver Broncos’ Von Miller, the Raiders’ Khalil Mack and the Kansas City Chiefs’ Justin Houston.

But the Jaguars present what Chargers coach Anthony Lynn calls “the biggest challenge of the season,” and not just because of a front four that was fortified by the recent acquisition of 6-foot-3, 331-pound Marcell Dareus from the Buffalo Bills.

Jacksonville features a trio of fast and physical linebackers in Telvin Smith, Paul Posluszny and Myles Jack and a swarming secondary that in Week 5 had a franchise-record five interceptions, two returned for touchdowns, against the Pittsburgh Steelers.

According to NFL Research, three Jaguars defenders rank among the top six in passer-rating allowed in coverage with a minimum of 20 targets — safety Tashaun Gipson (30.3) and cornerbacks Jalen Ramsey (38.2) and A.J. Bouye (40.4).

“The guys up front are winning battles, winning one on ones,” Jacksonville coach Doug Marrone said on a conference call. “But the guys in the back end, and that includes the linebackers, they’re really doing a good job of forcing the quarterbacks to hold the ball.

“If you study our stats, some are for the defensive linemen and some are coverage sacks. We’re probably 50-50. It’s really a group effort.”

The 6-8, 300-pound Campbell usually plays the edge in a 4-3 scheme but often moves inside on obvious passing downs, with the smaller and quicker Fowler (6-3, 255) and Ngakoue (6-2, 246) coming off the edge.

Responsibility for blocking Campbell in passing situations will fall to Chargers guards Dan Feeney, who will be making his second NFL start, and Kenny Wiggins, in his first year as a starter, as well as third-year center Spencer Pulley.

“He moves around a lot and does a good job of trying to get mismatches, so we’ll have to watch his tendencies and game-plan for him,” Feeney said. “We definitely have our work cut out for us. They’re big, strong and physical. It will be a good trench game, for sure.”

The Chargers will need to be precise in their execution, keep the chains moving and minimize third-and-long plays.

“We can’t let them pin their ears back and just rush us,” Wiggins said. “We have to have a balanced attack and protect well. Hopefully the play-action passes will slow them down, keep them guessing.”

Etc.

Lynn said that Denzel Perryman, who sat out the first eight games after ankle surgery, will start at weakside linebacker instead of his usual middle linebacker spot at Jacksonville, with Hayes Pullard remaining in the middle. “It’s easier to work Denzel in that way,” Lynn said, “and Hayes has done a good job at the [middle linebacker] position.” … Pullard (neck) and Pulley (knee) were limited participants in Wednesday’s practice, but right tackle Joe Barksdale, who has been slowed for weeks by turf toe, was a full participant.

mike.digiovanna@latimes.com

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