As both sides deal with critical injuries up and down the field, particularly at wide receiver, the Green Bay Packers and Chicago Bears start their 2015 campaigns and renew their rivalry Sunday afternoon at Soldier Field.

As if losing their No. 1 receiver before the start of the regular season wasn’t a great enough obstacle, the Packers head into their season opener against the Bears with questions surrounding new top target Randall Cobb.

Cobb’s been limited in practice throughout the week as he works through a shoulder sprain and tries to ascend as quarterback Aaron Rodgers primary weapon after Jordy Nelson was lost for the season with a torn ACL. Cobb was hurt against Philadelphia when he fell to the ground and a defender landed on top of him in the third game of the preseason. He sat out the final preseason game and has rested ever since, but Cobb expects to deal with some pain as Green Bay begins the season as one of a handful of Super Bowl favorites.

“Obviously, I’m going to be dealing with a lot of pain, but that’s part of it,” Cobb told reporters Wednesday. “I’m just going to work through this week and try to get ready. I have to be out there for my teammates.”

Cobb put up career numbers across the board last season, accumulating 91 receptions for 1,287 yards and 12 touchdowns, nearly a third of Rodgers’ overall production.

After finishing last season a mere two plays away from the NFL title game, the Packers are gunning for their fifth straight NFC North crown but are also dealing with two critical injuries at linebacker and in the secondary.

Linebacker Sam Barrington, who was expected to be a major contributor this season beside Clay Matthews in his third season, was limited in Wednesday and Thursday’s practices because of an ankle injury. How he fares until kickoff and in the early stages of the game, should he actually play, will likely determine whether rookie Jake Ryan makes his debut or if veterans Mike Neal or Nick Perry are asked to make plays.

Starting strong safety Morgan Burnett has held out of practice all week with a calf injury, which he sustained in the last preseason game against New Orleans.

With Ha Ha Clinton-Dix is expected to feature heavily in defensive coordinator Dom Capers’ schemes this season, the Packers could go without Burnett and tab Micah Hyde or fourth-year safety Sean Richardson.

Meanwhile, the Bears enter the game far more banged up with eight listed on the official injury report, including quarterback Jay Cutler’s top three receivers.

Wide outs Alshon Jeffery (calf) and Eddie Royal (hip) have participated in practice on a limited basis this week, with Jeffery’s injury of most concern now that he’s expected to takeover for the since-traded Brandon Marshall. But even though he was limited, Jeffery’s appearance at practice was a good sign since he’s been sidelined for a month by the aching left calf.

The eight-year veteran Royal was originally supposed to play between the second or third receiver role, but with rookie Kevin White potentially out for the year, Royal’s injury comes at a poor time for the Bears. Marquess Wilson (hamstring) has also been limited all week.

Injuries have also affected the Bears' defense. Cornerback Tracy Porter (hamstring) and rookie defensive lineman Eddie Goldman (concussion) are the two key starters on this week’s injury report, with Porter especially critical given Rodgers ability to pick apart defenses.

Goldman, however, fully returned to practice on Wednesday since passing the NFL’s return-to-play protocol after suffering a concussion against Cincinnati the preseason finale. The second-round pick takes over for suspended nose tackle Jeremiah Ratliff.

Kickoff Time: 1 p.m. ET

TV Channel: FOX

Live Online: NFL Game Pass