The NFL's oldest rivalry kicks off Sunday when the Chicago Bears (2-1) host the Green Bay Packers (1-2) at Soldier Field.

The Bears enter the contest riding a two-game winning streak, while the Packers are coming off a loss to the Detroit Lions.

Here, ESPN Bears reporter Michael C. Wright and Packers reporter Rob Demovsky break down key elements leading up to Sunday's matchup.

Wright: Rob, there seem to be tons of questions regarding Green Bay's struggling offense. But what perked up my radar is Aaron Rodgers and coach Mike McCarthy seemed to contradict one another about some of the things that went wrong against Detroit and what adjustments the offense needs to make moving forward. It seems Rodgers and McCarthy have butted heads in the past about the offense. What's going on now?

Demovsky: Rodgers doesn't say anything without carefully thinking it through, so clearly there was something that bothered him about what they tried to do offensively against the Lions. That was not just an off-the-cuff remark, not when he kept using the word "adjustments" over and over. The interesting thing is, McCarthy has been criticized in the past for not sticking with the running game long enough, but against the Lions, it might have been the opposite. He stayed with the running game long after it was apparent they couldn't get anything done on the ground. Rodgers also mentioned the fact that perhaps they need to move receiver Jordy Nelson around in order to gain favorable matchups, but they did that some against Detroit -- including on the fourth-and-5 play in the red zone on which Nelson got matched up against a linebacker, and Rodgers simply missed him.

Turning to Chicago, perhaps the two highest profile signings in the NFC North were the Packers signing Julius Peppers and the Bears signing Jared Allen. Peppers had his best game as a Packer last week against the Lions, and the coaches seem pleased with his contributions. How are the Bears feeling about what Allen is giving them?

Wright: Statistically, Allen obviously got off to a slow start with two tackles in each of the first two games, but against the New York Jets on Monday night, Allen put together somewhat of a breakout performance with seven stops. The Bears are certainly pleased with Allen's contributions up to this point, but I also think the staff's feelings concerning the defensive end are more about his contributions at practices and in the meeting rooms. Remember, originally, the Bears brought in Willie Young to start opposite Lamarr Houston. Then, Allen sort of just fell in the team's lap in free agency and it had to pounce. Allen has been instrumental, in my opinion, on helping to develop Young, as well as some of the other players. Don't be surprised if Young eventually becomes one of this league's better defensive ends in the next couple years, and Allen will have had a part in that. Allen mentioned last week that ever since he left the Kansas City Chiefs, he's typically gotten off to slow starts statistically. This season appears to be no different. But the staff still is pleased with Allen.

I know Green Bay faced imposing defensive lines to start off in Seattle, the Jets and the Lions. Are this team's struggles along the offensive line a product of the teams they faced or are there real problems in protection?

Demovsky: We should find that out this week, right? It looked like the Bears did a decent job against the Jets' running game, but they still rank 26th in the league in run defense. If the Packers can't get Eddie Lacy going against this defense, then there are real problems. The interesting thing is James Starks has been able to make things happen on the ground, whereas Lacy has not. Perhaps that's why McCarthy put the onus on Lacy this week, when he said "Eddie needs to play better."

The Packers have struggled to run the ball, too, but what in the world is wrong with the Bears' running game?

Wright: Man, I think the Bears suffered from the same thing as the Packers in that they drew tough opponents for the first three contests. Think about it: All of Chicago's first three opponents rank among the top 10 in rush defense. The Jets ranked No. 1, the San Francisco 49ers are seventh and the Buffalo Bills sit at No. 6. Combine that with the fact the Bears lost starting center Roberto Garza and left guard Matt Slauson and have played the past two games with Brian de la Puente and rookie Michael Ola in those spots. In my opinion, playing the backups sort of throws off the precise timing needed to really click in the ground game.

Let's look at Green Bay's air attack. Randall Cobb and Nelson combine for 58 percent of the Packers' offense. So it looks to me like the complementary targets aren't getting it done. What does Green Bay do if the Bears find a way to take away Cobb and Nelson, especially considering this team's struggles the first three weeks running the ball?

Demovsky: It would help if they could get their tight ends involved. Remember all those catches Jermichael Finley used to make against the Bears? That's one of the things that has been missing from this offense. The Packers hoped rookie third-round pick Richard Rodgers would be able to make an immediate impact, but despite starting all three games so far, he hasn't caught a single pass. Of course, Rodgers has only thrown his way once. Andrew Quarless seemed to take over the role midway through the game against the Lions and had the Packers' only touchdown of the game, but he's not as dynamic as Finley. They probably need to turn to Brandon Bostick, who looked like Finley-lite in the preseason before he sustained a leg injury. He's back healthy again but mysteriously hasn't played on offense in the past two games despite appearing on special teams.

While the Packers seem to be a team lacking confidence, how sky-high are the Bears after winning back-to-back road games -- one on each coast against the 49ers and Jets?

Wright: Confidence is definitely sky-high, my man. When the Bears upset the 49ers on the road, coach Marc Trestman talked about how wins such as that are the ones that build a strong backbone for later in the season, when every outing is clutch. Remember, coming into the season, everyone expected the offense to carry the defense. But in the two wins on the road, it was the defense shouldering the load for what's been a fairly mediocre offense. So the Bears know they've got a really good shot to put it all together at some point. But injuries are certainly a concern. The Bears play five of their first seven games on the road, and I still contend they'll be lucky to go into the Nov. 2 bye week with a record of better than .500.