The 5: Cardinals face Chargers with eyes on lines, Chris Johnson’s debut

The Arizona Cardinals have much to gain in their second preseason matchup.

Hosting the San Diego Chargers at University of Phoenix Stadium, Bruce Arians’ squad will begin searching for capable injury replacements along the lines. The losses of Mike Iupati on the offensive line and Corey Peters on the defensive line loom large, but Arizona also has new position players to throw into the mix.

More on that and what else we’re looking forward to in the matchup Saturday.

Back by committee

After Andre Ellington left the field following a handful of snaps — and a spectacular 57-yard receiving play — in the preseason opener, the Cardinals weren’t left with much to work with at running back. This week will be different.

Ellington will again run with the first team, but free agent signee Chris Johnson and rookie David Johnson will be available to head coach Bruce Arians.

Update: The Cardinals announced Chris Johnson will not play Saturday. It’ll be the first glimpes of how far along Chris Johnson is in his recovery after a drive-by shooting left the running back with a gun-shot wound in his shoulder this March. David Johnson, who has been out with a hamstring issue, returned to practice this week and — despite playing catch-up — impressed with his receiving skills out of the backfield.

Another change to the O-line

Last week, all eyes were on the offensive line depth because of Bobby Massie’s suspension due to a DUI arrest. The worry about protecting quarterback Carson Palmer remains something to watch this week after the Cardinals learned left guard Mike Iupati will require surgery to repair a meniscus injury in his knee.

More will be placed on Bradley Sowell at right tackle, while Ted Larsen and Earl Watford will try to get a step ahead in place of Iupati.

Gunter at nose

The offensive line wasn’t the only front needing to apply the “next man up” theme. Nose tackle Corey Peters was lost for the season because of an Achilles tear, and the coaching staff is using the injury to give rookie Rodney Gunter, Arizona’s fourth-round pick out of Delaware State, a chance to shine.

Alameda Ta’amu and undrafted rookie Xavier Williams will also see time at nose tackle.

Steps forward for Thomas?

Logan Thomas may be fighting for the third-string quarterback job, but if last year was any indication, Arizona would feel much better about its depth if it had a capable third signal-caller.

Thomas compiled 107 yards and an interception on 9-for-15 passing in the team’s first preseason game. The performance wasn’t terribly good nor bad, but Thomas stringing together consistent games would give Arians more confidence that, if called upon, the Cardinals can count on him.

Chargers’ top pick likely out

Melvin Gordon, the 15th overall pick in the 2015 draft, returned to San Diego practice Thursday after suffering a minor ankle injury. He said he’s ready to go against the Cards, but the coaching staff is cautious about playing the first-round pick.

Arizona’s run defense will nonetheless be challenged. In San Diego’s preseason opener, Gordon only rushed six times for 11 yards, yet the rest of the Chargers running backs put up another 124 yards on 38 carries in a 17-7 win against the Cowboys — three quarterbacks combined for just 20 pass attempts.

Time

7 p.m. MST

TV

ABC 15, NFL Network (national)

Radio

Arizona Sports 98.7

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