Cam Newton's shoulder could be getting a rest. (Grant Halverson/Getty Images)

It’s one of the most important questions facing an NFL franchise, and one for which there is no clear formula. When is it a good idea to bench a star player for the rest of the season, whether for his own well-being or because the season is lost?

Sometimes, a combination of circumstances makes the choice a no-brainer. But the computation becomes more complex when the players involved are quarterbacks, and exponentially more so when the players are former NFL MVPs.

Which brings us to Cam Newton and Aaron Rodgers. Both have been dealing with injuries they’d prefer not to discuss in detail, and both have said they planned to play the final two games of the season. However, Newton missed practice Wednesday and Carolina GM Marty Hurney later confirmed that Newton won’t play against the Atlanta Falcons Sunday, with backup Taylor Heinicke starting instead. Newton is also expected to sit out Carolina’s finale against the Saints, according to the Charlotte Observer’s Jourdan Rodrigue and other reports, although Coach Ron Rivera said Newton will remain on the 53-man roster.

“We had the opportunity to visit with the doctors, the trainers and Cam himself,” Rivera said on Wednesday, via ESPN. “In talking with Marty and [owner David Tepper], obviously we felt our best opportunity to win a football game was to have a healthy Taylor to start this week.”

Newton has appeared limited for weeks, but the Panthers, despite losing their sixth game in a row Monday night, still have a faint chance of making the playoffs. Newton, who has been on a “pitch count” when passing in practice for most of the season, has dealt with shoulder injuries over the past several years. He took a beating during the 2016 regular season and had surgery in the spring of 2017. It’s seemed clear in recent weeks that his shoulder is bothering him again, and he’s appeared to struggle completing passes beyond 10 years downfield. The Panthers are 6-8 and would need significant help to get a wild-card berth. And Newton either isn’t saying or doesn’t know what the problem is.

“No matter how much you push, no matter how much you ice, the anti-inflammatories you take. Trust me, I’ve done it,” he said Monday night. “Acupuncture, massages. There’s not a night that goes by without me getting some type of work done on my arm. You just don’t have the strength.

“From the range of motion, you work on the range of motion, then come[s] game time and you never know how the game can play out. Of course you try to stay under 25-30 throws, but if you surpass that or you get hit on it, or you have to run, or you get tackled and fall on your shoulder, certain things happen.”

Rivera said Newton understood the team’s decision, but that “he’s disappointed, he’s frustrated, he wants to play.” Kyle Allen will be promoted from the practice squad to back up Heinicke, according to Hurney, the GM.

For Rodgers, the decision about whether to play is simplified by the fact that the Packers have been eliminated from playoff contention, and complicated by the fact that football players — especially ones who, like Rodgers, are among the NFL’s highest-paid players — want to play. The message his sitting out would send to lesser-regarded teammates could be detrimental.

“It’s about leadership; how can I stand here and say these games don’t matter,” Rodgers said Wednesday, via The Athletic’s Josh Tolentino. “That’s not the way I lead. I’m super competitive.”

It’s a message his teammates likely appreciate.

“When I signed a contract,” Green Bay offensive lineman David Bakhtiari said Sunday, “it didn’t say ‘play until you’re out of the playoffs.’ No, I get paid to play 16 games and the playoffs are a bonus.”

The variables for Rodgers have included a knee injury he suffered in the opener and a groin injury that tightened up on him against the Chicago Bears this past week. And if interim coach Joe Philbin and Packers management would rather see what they have in backup DeShone Kizer, Rodgers might have a problem with that.

“Yeah, probably,” Rodgers said Sunday with a smile, then added, “No, look, nobody’s talked to me about it.

“I want to play, though, so I’m expecting to start and play,” Rodgers said then. " In 2005, I remember [Brett] Favre came in late in the season and said, ‘Well, you’re probably going to get a chance to play here.’ It didn’t happen. Now, Brett was 36, I think, at the time. I’d like to be out there and lead us the last two weeks.”

His stats have been solid this season, but throwaways, missed receivers and the inability to deliver in the clutch have helped cause his team to limp to a 5-8-1 record. His goal, if he plays? “I think a good one is probably we can get our first road win of the year,” he said of Sunday’s game against the New York Jets.

That may not be enough for management, though. Philbin says he would “never put any player out there that wasn’t physically ready to go,” but some players have a larger say in their availability than others. “Finishing is important. Doing things the right way is important,” Philbin said Sunday. “It’s a lesson for them that hopefully they can take beyond football.”

Those “certain things” that Newton mentioned are especially tricky for coaches who, like Rivera and Philbin, face uncertain futures of their own. There has been a buzz about whether the Panthers' new management might want to part with Rivera; Philbin, meanwhile, became Green Bay’s interim coach after the firing of Mike McCarthy on Dec. 2.

There also is the unstated pressure that comes from working in a league that is driven by TV ratings. The simple fact is that, even on Week 16 with little or nothing at stake, viewers want to see Rodgers and Newton, not Kizer and Heinicke.

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