All eyes will be on starting quarterback Mike Glennon and the Bears' first-team offense when they get a second chance to make a good impression Saturday night against the Cardinals in Arizona.

Glennon has nowhere to go but up after posting a 0.0 passer rating in limited playing time in his Bears debut on Aug. 10.

He is expected to get a longer look this week, when the quarterbacks will appear in the same order as they did in the preseason opener. Glennon was followed briefly by veteran Mark Sanchez and then rookie Mitch Trubisky, who got the majority of the playing time in the opener.

While the order won't change, the playing time probably will.

Glennon needs more time to demonstrate a stronger rapport with wide receivers Cam Meredith and Kevin White, if for no other reason than to tap the brakes on the runaway belief that Trubisky should be the starter after his impressive debut.

Another successful outing by Trubisky could turn a quarterback conversation into a full-blown controversy.

"We have a lot of things to fix," Meredith said of the first-team offense after the Bears' Thursday night practice at Prospect High School. "We went back and watched the film. Our passing game wasn't quite how we liked it. We fine-tuned some things, and throughout the week fixed a lot of things."

Meredith was targeted twice in Week One but had no receptions, as Glennon completed just 2 of 8 passes for 20 yards. White was not targeted.

"We try to stay encouraging for Mike, and we don't listen to the outside noise too much," Meredith said. "It's all about internal things. We got some things figured out, and we're all looking forward to this game."

Glennon is far from the only member of the first-team offense who needs to show improvement.

The offensive line bears watching as well. It will be without left guard Kyle Long (ankle), who appears doubtful to be 100 percent by the start of the regular season. The O-line depth has already suffered a hit when Eric Kush, the top backup at both guard spots, was placed on injured reserve with a torn hamstring last week.

Now, inexperienced Will Poehls and Cyril Richardson are listed as the backup guards. But, since Kush's injury, the Bears have been experimenting with center Hroniss Grasu at guard as well. Grasu, a third-round pick in 2015, was the starting center last year until he suffered a season-ending knee injury in the preseason.

On the Bears' most recent depth chart, Grasu is listed as the backup center to Cody Whitehair, but he is not listed at all among the guards.

"We're gonna play him at both," coach John Fox said. "He's gonna have to know both, he's gonna have to have reps at both."

Typically teams have just seven offensive linemen active on game days in the regular season, so the two backups must be able to play more than one position.

If Long is unavailable when the regular season begins, one of the backups must step in as a starter.

One possible scenario involves putting Grasu at center and moving Cody Whitehair back to his original position at guard, even though he played extremely well last season when thrown in at center one week before the regular season started.

Defensively for the Bears, the focus is on the shuffling going on in the back seven. Inside linebacker Danny Trevathan is way ahead of schedule after last year's torn patellar tendon, but he's not ready for game action yet.

Nick Kwiatkoski, a fourth-round draft pick last year, has been playing in Trevathan's spot and has shown marked improvement from his rookie season. But Kwiatkoski is still limited after suffering a concussion in the preseason opener. That means increased reps for Christian Jones and John Timu.

In a revamped secondary, veteran free-agent signees Marcus Cooper and Prince Amukamara are the starters. Amukamara (hamstring) may be limited and nickel corner Bryce Callahan (hamstring) is not expected to play. So Cre'Von LeBlanc, who is competing for the nickel corner spot with Callahan, could see additional playing time on the outside, along with Kyle Fuller, who is hoping to remain relevant after a 2016 season lost to injury.

Veteran free-agent Quintin Demps is locked in at one of the safety spots. But incumbent Adrian Amos must hold off rookie Eddie Jackson and 2016 fourth-round draft pick Deon Bush to keep his job.

Other Bears not expected to play vs. the Cardinals are guard Kyle Long (ankle), linebackers Danny Trevathan (knee), Jonathan Anderson (ankle) and Alex Scearse, running backs Jordan Howard (eye) and Jeremy Langford (ankle), wide receivers Josh Bellamy (ankle) and Markus Wheaton (finger), and defensive linemen Mitch Unrein (concussion) and Kapron Lewis-Moore.

Howard suffered what the Bears said was a "minor" scratched cornea in Friday's walk-through.

• Veteran free-agent linebacker Kelvin Sheppard was signed and undrafted rookie linebacker Hendrick Ekpe was waived. The 6-foot-2, 249-pound Sheppard started 11 games and had 50 tackles last season for the New York Giants. He had his best season in 2015, when he had 105 tackles as the starting inside linebacker for the Miami Dolphins.

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