Bill Belichick is moving on to UNC. Funny, Nick Sirianni is likely to outlast him with the Eagles.

Nick Sirianni’s job is more secure than Bill Belichick’s. Could you have imagined suggesting such a thing 11 months ago? But it’s true, and the fact that Belichick has officially been in his job — as the head coach at the University of North Carolina — for just a couple of days doesn’t change that truth.

Does this mean Sirianni is a better coach than Belichick? Of course not. There is a strong case to be made that Belichick is the greatest football coach ever, though that case got harder to make once he and Tom Brady were no longer together in New England. What it means is that being a head coach in the NFL and being a head coach in college football — in the name, image, likeness, and pay-for-play era of college football — are different things. And it might just be that Belichick will struggle in either of those worlds.

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Take the NFL first. When it comes to the manner in which teams are coached, the same term applies: system-based. Whether it’s the head coach (e.g. Andy Reid, Sean McVay, Kyle Shanahan, Sean Payton) or the people above him (e.g. Jeffrey Lurie and Howie Roseman) implementing and overseeing it, the system or philosophy is king. The Eagles are a perfect example of this concept. Lurie and Roseman have a certain way they want the Eagles to play, a certain way they want things done, and Sirianni and his staff are the vessel for it. When that system doesn’t function properly (as it didn’t in 2020 under Doug Pederson; as it didn’t for the final seven weeks of last season), Lurie and Roseman replace the head coach and/or the people under him. When it does (like in most of Reid’s and Sirianni’s tenures here), the head coach can feel pretty safe.

The college game remains amid so much upheaval that it’s difficult to know what the prevailing philosophy for success will or ought to be — beyond Let’s throw a ton of NIL money at these kids, of course. Will head coaches generally turn out to be the most powerful people in the most powerful programs? What about the general managers so many of these programs are hiring? What about the boosters and alumni? In a sport without a salary cap, does a system — how a team plays and why it plays that way — matter nearly as much as the program’s financial resources?

Back to Belichick. With the Patriots, he didn’t implement a system. He was the system. He acquired the players, coached them, then tended to cast them aside before they overstayed their welcomes. (He wanted to do the same with Brady. He’s fortunate for his legacy that his plan failed.) His brain and instincts determined the team’s every course of action, and his involvement was total, so consuming, that he often rendered his assistants and advisers mere accessories.

This was a big reason, maybe the biggest, that NFL franchises, the Eagles included during their period of uncertainty about Sirianni, hesitated to hire Belichick once he became available. You bring him in, and you’re in his shadow, no matter who you are and how much power you might have had. It was telling that, according to an ESPN story this week, Belichick had kept in close contact with a small group of confidants since Patriots owner Robert Kraft fired him after last season — and that none of those confidants was employed in the NFL. Without Belichick’s imprimatur, Matt Patricia hasn’t been much more in the league than a guy who happens to wear a beard, a backward baseball cap, and a pencil in his ear.

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As for his new role at UNC, is the pull of his past, of the coach he once was and might still be, really going to be enough to attract players? Is it going to be enough to motivate them and keep them there once they get the full flavor of his personality and style — the biting insults and grumpy-Gus discipline that older men put up with in the name of winning but likely will make younger men roll their eyes and run for the transfer portal?

Bill Belichick is 72. He went 29-38 over his final four years in New England, including a 4-13 bus crash last season. The last playoff game he won was Super Bowl LIII, which will be nearly six years in the distance by the time he coaches his first game for the Tar Heels. He might thrive in Chapel Hill. He probably won’t. Either way, he’s just a hired gun, and those kinds of guys, even if they do their jobs, don’t stay in town long.

The Eagles play in Week 15 against the Pittsburgh Steelers. Join Eagles beat reporters Olivia Reiner and EJ Smith as they dissect the hottest storylines surrounding the team on Gameday Central, live from Lincoln Financial Field.