CHARLOTTE, N.C. -- Nobody can say exactly what play or game Cam Newton's right shoulder was re-injured to the point he couldn't be effective, or whether it even was one play versus the typical wear and tear that goes with a season.

But when you start looking for reasons the Carolina Panthers (6-9) went from 6-2 and a Super Bowl contender to inconsequential and potentially a top-10 draft selection, Newton's shoulder is the place to start.

It's not the only reason the Panthers are on a seven-game losing streak heading into the finale in New Orleans (13-2), the top seed in the NFC. The defense has fallen well short of expectations and the offensive line has been a mess since the start of training camp.

"As a team our production dropped," said Pro Bowl tight end Greg Olsen, who has been limited to nine games because of multiple injuries to his right foot. "There's a lot of factors that go into it. Every player shares a role. This isn't basketball. You can't roll the ball out to LeBron and let him go.

"There are a lot of guys that have to do their job to have success or failure."

Olsen also doesn't think the unprecedented collapse if the Panthers go on to finish 6-10 is a good reason to blow up the coaching staff and start anew.

"This year was a huge disappointment," Olsen said. "I don't think anybody in this locker room would say otherwise. I don't think any of the coaches would say otherwise. That's a pretty consistent narrative that everybody has shared. But to think we would get better by making rash changes would be the easy thing. That's very emotional. Every time people struggle the reaction is something has got to be better."

Change is coming. Coach Rivera has said repeatedly lately that everyone is being evaluated, from players to coaches to himself. He's made it clear he's not sure what owner David Tepper is thinking in terms of the staff, saying it has not been communicated to him that he'll be back for a ninth season even though the feeling inside Bank of America Stadium is Rivera and general manager Marty Hurney are safe.

"You can't ask me questions that I don't know the answer to," Rivera said.

But you can start looking at where things went wrong. And when a team lives by the mantra "as Cam Newton goes, so go the Panthers," the shoulder that has the 2015 NFL MVP shut down for the final two games has to be a factor.

It's definitely a factor as the Panthers move forward with a plan to rehab the shoulder, likely through rest with a second surgery in two offseasons not entirely out of the equation. The uncertainty makes finding a solid backup and possible successor to Newton through free agency or the draft a priority.

That's why the Panthers likely will be evaluating Teddy Bridgewater, who is likely to replace quarterback Drew Brees Sunday with the Saints' playoff seeding secured, as much as they will their own starter, Kyle Allen. Bridgewater played under Carolina offensive coordinator Norv Turner in Minnesota.

"You have to be somewhat concerned," Turner said of Newton's future. "There's going to be a sense of urgency addressing it. He'll get the best medical treatment he can get. He went a pretty good stretch where he was playing at a really, really high level. We've just got to do whatever it takes so we can do it for an entire season."

Let's take a closer look at three things that led to the team's downfall:

The shoulder: The Panthers began limiting Newton's throwing in practice after he threw 22 times in the fourth quarter of a comeback win at Philadelphia on Oct. 21 that got the Panthers to 4-2. The Panthers won their next two games to get to 6-2, with Newton throwing four touchdowns to no interceptions and having a passer rating of 101 or more in both. So you have to say the shoulder issue wasn't critical then. Then came a 52-21 Thursday night drubbing in Pittsburgh, when Newton began a streak of six straight games with at least one pick after having only four in the first eight. Even in that game, and the ensuing losses to Detroit and Seattle, Newton had a passer rating of 110 or higher.

Then came the Tampa Bay loss on Dec. 2. Newton said midweek prior he was playing the best football of his career. Turner agreed. Then Newton threw four interceptions in a 24-17 setback that started three consecutive games of a passer rating below 70. Newton was sacked four times and hit nine times against Tampa Bay. Twice he was hit while in the process of throwing to send the ball fluttering for interceptions. The Bucs took a page from the Pittsburgh game plan in making Newton uncomfortable. Whether one of those hits made Newton's shoulder uncomfortable the next two games no one will say for sure, but he clearly wasn't the same afterward.

His final game, a 12-9 loss to New Orleans, was most telling. Newton badly underthrew 6-foot-4 receiver Devin Funchess in the end zone when the Panthers had a chance to pad a 7-6 halftime lead. He skipped even short passes late in the game, and was shut down the next week after a season-low 52.5 passer rating.

"He fought his ass off," Olsen said of Newton. "He did everything physically possible to go out there and play with the state of his shoulder. He gave us everything he had. We've seen that for eight years. I don't think that was an a-ha moment."

But being shut down the past two weeks was.

The defense: Rivera talks a lot about the importance of continuity. Perhaps that caught up with the defense when Eric Washington, Carolina's defensive line coach, became Carolina's third coordinator in three years. Call it the trickle-down effect. Washington, who had been considered one of the best D-line coaches in the league, was replaced by former Michigan coach Brady Hoke. The strength of former defensive coordinator Steve Wilks, named the head coach at Arizona during the offseason, was the secondary. Jeff Imamura was hired to coach the secondary well into the offseason when secondary coach Curtis Fuller resigned amidst an internal investigation into workplace misconduct.

That Rivera fired Hoke and Imamura, and took over the defensive playcalling after the loss to Tampa Bay, was telling. But you can't blame this all on the coaches. The players, in large part, underperformed. Defensive end Julius Peppers admitted late in the season that the chemistry wasn't there.

Inconsistency in the pass rush (Carolina ranks 25th in sacks with 33), trouble getting off the field on third down (the Panthers rank 20th in third-down efficiency) and the inability to limit big plays over the top were problems even during the fast start.

"We didn't get the job done," safety Eric Reid said. "At the end of the day it comes down to execution. Coaches calling the plays, the players executing. We didn't get it done is what it all comes down to."

The offensive line: The rash of injuries to the offensive line began in training camp when right tackle Daryl Williams went down early with a knee injury. By the time the season began without left tackle Matt Kalil, who spent the entire season on injured reserve with a knee injury, only center Ryan Kalil and right guard Trai Turner were at the same position they began camp in. Turner then missed the second and third games with a concussion.

Because Newton was getting rid of the ball quicker than he had at any time during his career and making running back Christian McCaffrey into arguably the best all-purpose back in the league, the mistakes were covered up by winning. But as Newton wore down and was less of a threat as a runner, the protection wore down as well. After giving up 14 sacks during the 6-2 start, the Panthers gave up 19 over the next seven games. Pittsburgh might have shown the formula for slowing Newton, sacking him five times and making sure he wasn't a factor as a runner.

As the team approaches the offseason, with Ryan Kalil retiring and uncertainty around his brother, left tackle Matt Kalil, the Panthers could be looking at three to four new starters up front in 2019.

Olsen's situation further complicates matters. He's gone from the first tight end to have three consecutive 1,000-yard receiving seasons (from 2014 to 2016) to 44 catches for 482 yards the past two seasons combined. As much as the Panthers like rookie tight end Ian Thomas, a healthy Olsen would help.

But the biggest issue moving forward remains Newton's shoulder.

"There's a sense of urgency right now to have an exact plan for Cam and diagnoses of where he is at," Norv Turner said. "We certainly wouldn't want to get caught in this situation again."