Last year, ESPN's rankings of the biggest names in sports listed Cam Newton as the fourth-most famous player in the NFL, behind only Tom Brady, Drew Brees and Odell Beckham Jr. That'd make him the most famous millennial-aged quarterback in the world.

He has 4.1 million Instagram followers, 1.9 million Facebook fans and 1.1 million followers on Twitter.

Despite playing in the 23rd-largest media market in the United States, and despite coming off a tough, injury-derailed season, Newton remains a damn big deal. The Carolina Panthers can't afford to lose him, and the NFL as a whole would suffer without him.

When Newton went down with a foot injury in a preseason game Thursday night against the New England Patriots, you could assuredly hear pins drop in team owner David Tepper's suite, in commissioner Roger Goodell's living room and in dens throughout the Carolinas.

Now, Newton might be OK. This time. The 2015 NFL MVP left Gillette Stadium in a walking boot, but general manager Marty Hurney told reporters Friday the team is "cautiously optimistic" Newton will be ready for a critical Week 1 matchup with the Los Angeles Rams on Sept. 8.

The injury took place on what appeared to be an innocuous play three series and 11 snaps into a meaningless game. It highlights the increasingly popular notion that whatever rewards can be reaped from preseason reps aren't worth the risk associated with that playing time.

It's simple. The more live snaps a player participates in, the higher his chances are of getting hurt. And in a day and age in which players typically train hard 12 months a year, preseason snaps have lost most of their value.

New-age head coaches Frank Reich of the Indianapolis Colts and Matt Nagy of the Chicago Bears have already said they'll break from tradition by resting their starters when their teams face each other Saturday in what would normally be an unofficial dress rehearsal. Newton's scare should only inspire more coaching staffs to consider that approach.

The NFL, which faces an uphill battle in fighting for the hearts of millennial fans, needs its superstars on the field. With Newton, the Panthers are utterly intriguing. Without Newton, they're tragically uninteresting.

Part of the problem is that there's not much of a contingency plan in Carolina.

Eli Manning is a big name, but if he goes down, the New York Giants arguably become more interesting with rookie No. 6 overall pick Daniel Jones. Teams like the Green Bay Packers, Pittsburgh Steelers and Dallas Cowboys draw off-the-charts interest regardless of who's under center. But take Newton away from the Panthers (or Russell Wilson away from the Seattle Seahawks, or Deshaun Watson away from the Houston Texans), and a captivating team drops from casual fans' radar.

Injuries happen, but another significant injury to Newton would be one of the worst potential scenarios for the league. We saw when he won MVP and took the Panthers to the Super Bowl in 2015 that he's the type of star player capable of carrying his team on his back.

Newton is a 6'5", 245-pound one-of-a-kind quarterback with 4.6 speed who has an MVP, three Pro Bowls and a Super Bowl appearance on his resume. Only three running backs have more rushing touchdowns than him this decade, and he ran for nearly 500 yards in 14 games last season.

But when he wasn't healthy thanks to a balky throwing shoulder down the stretch last year, a Panthers team that lacked talented reserves at the quarterback position crashed and burned. Carolina started 6-2 and was still 6-5 when Newton's play began to decline sharply. He played three more games and missed the final two, backup Taylor Heinicke struggled mightily in a Week 16 spot start and the Panthers went 1-4 during that stretch.

Heinicke and fellow returning backup Kyle Allen haven't proved to be viable options to relieve Newton for an extended run. Those two have completed just 53 percent of their passes this preseason, mainly against defensive scrubs. Their combined passer rating is 73.3. Rookie third-round pick Will Grier has a higher ceiling, but his preseason numbers are worse, and it appears he requires a good deal of development.

Would a strong performance from Newton on Thursday have caused anyone to heighten their expectations for the Panthers this season? Did three offensive series from the starters benefit the Panthers enough to increase their eventual win total for 2019? Again, this is about risk and reward; in that light, it's hard to justify letting megastar quarterbacks hit the field against hostile defenses in August.

The Panthers have the talent to win a Super Bowl. Newton is one of the most uniquely talented players in the history of the sport, and he's in his prime at age 30. He's also better-supported than ever as youngsters Christian McCaffrey and DJ Moore become stars at running back and wide receiver, respectively. He's got three-time Pro Bowl tight end Greg Olsen and strong right tackle Daryl Williams back from injury, and third-year receiver Curtis Samuel has been a revelation this offseason.

But none of that matters if Newton can't get—and stay—healthy. We received a stark reminder of that fact Thursday evening.

Brad Gagnon has covered the NFL for Bleacher Report since 2012.