Bill Belichick, Jim Harbaugh among the NFL's most indispensable coaches

In the reports of tension earlier this week between San Francisco 49ers head coach Jim Harbaugh and the team's front office (specifically general manager Trent Baalke), there was this interesting tidbit from NFL.com's Mike Silver:

As much as [CEO Jed] York and his top executives value Harbaugh and appreciate the swift and sublime success he has enjoyed since arriving in 2011, a stretch that has included three consecutive NFC Championship Game appearances and a near-miss Super Bowl defeat, they are not inclined to beg him to stick around, either through words or emphatic financial gestures of support.

Yes, they like him, and acknowledge that he's very good at what he does. Sure, he is high-maintenance and at times demanding -- but they can live with that. What Harbaugh's bosses won't do is panic in the face of reports that he might be wooed to greener (as in the color of money) pastures, be they the University of Texas, the University of Southern California or the Capital of Creative Combine Questions.

"We didn't do that when we hired him in the first place, either," one top Niners official reminded me on Saturday, referring to the team's refusal to raise its offer to Harbaugh in the face of a late push (and reportedly sweeter deal) from Miami Dolphins owner Stephen Ross. "Why would we run scared?"

Well, one reason to run scared would be the Dolphins' current situation under head coach Joe Philbin, or any number of scenarios in which teams areblown apart by the simple fact that the man in the most publicly prominent leadership role doesn't know how to lead.  And the Cleveland Browns' recent attempt to trade for Harbaugh got us to thinking -- who are the league's most indispensable coaches? The coaches without whom NFL teams would be lost? Harbaugh's on that list, but there are a few names above his.

Bill Belichick, New England Patriots

Since he became the Patriots head coach before the 2000 season, Belichick has been the only constant through a decade and a half of unrivaled success. New England has won at least 10 games in all but two of Belichick's Foxboro seasons -- one was his first season there, and the second was 2002, when the team won nine games. The Pats managed to win Super Bowls in the years on either side of that "disappointment." You can talk about Spygate and the fact that there hasn't been a Super Bowl win since the end of the 2004 season, but Belichick has cycled through players, assistants and front office talent, with plenty of in-season success to show for it. And for that reason, no NFL head coach is more indispensable to his team.

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Pete Carroll, Seattle Seahawks

Here's an amazing stat: If the Seahawks cut defensive end Red Bryant in the next couple of weeks to alleviate their salary cap issues, nose tackle Brandon Mebane would be the only player left on the defensive side of the ball from before Carroll came to the Emerald City in 2010. That means Carroll and general manager John Schneider built the league's best current defense, and one of the best in recent years, from the ground up over a four-year period. One of the most underrated points about Carroll's current success as an NFL head coach, and perhaps where he failed in the 1990s with the New York Jets and the New England Patriots, is that his decade at USC allowed him to get a sure bead on the best college players based on his own thoughts about them when they were high-school recruits. From Percy Harvin to Richard Sherman, several key cogs on the Seahawks' roster are kids that Carroll wanted, but didn't get, out of high school.

Schneider is the personnel guy, but Carroll calls the shots, and he's assembled the youngest Super Bowl-winning team in NFL history. The way he's done it makes him just about impossible to replace.

Sean Payton, New Orleans Saints

It's a football truism that people, at times, show their true value in their absence. That was certainly true of Payton when he was suspended for the entire 2012 season for his role in the BountyGate affair, and the Saints plummeted from 13-3 to 7-9 in the year their head coach was gone. Payton has a rare and extremely productive relationship with quarterback Drew Brees, and that's no accident -- he understands the position as few coaches do, and his advanced route concepts allow just about any receiver to come into New Orleans' offense and succeed. Payton is probably the most indispensable offensive coach in the league today, and his control over his team adds a lot to the picture. When he hasn't controlled things -- well, you get what got him booted from the league for a season.

Jim Harbaugh, San Francisco 49ers

So ... contrary to what Baalke may believe, you can't just throw any half-decent coach at the 49ers and make them win. Because before they hired Harbaugh in 2011, management had thrown several half-decent coaches at the problem, and had little to show for it. The franchise hadn't had a winning season since Steve Mariucci's last year in 2002, and three men -- Dennis Erickson, Mike Nolan and Mike Singletary -- tried and failed in the decade after. Harbaugh, who had turnarounds at San Diego and Stanford on his resume, brought offensive coordinator Greg Roman and defensive coordinator Vic Fangio with him from Stanford, and immediately created a culture of success. In his three seasons, the 49ers have 41 regular- and postseason wins, tied with New England for the NFL lead. Harbaugh's personality may be grating, and he may not be long for the Bay Area as a result, but there's no denying his effectiveness as a head coach. And if the 49ers think they can plug another guy in without a diligent search, they're fooling themselves.

Marvin Lewis, Cincinnati Bengals

The Bengals have been eliminated in the wild-card round of the last three playoffs, but Lewis still gets the nod here because it's tough to imagine too many coaches would put up just three losing seasons in 11 years with an owner/general manager like Mike Brown, and a scouting department that only recently went beyond a pathetically low-staffed scouting department. In addition, Lewis has the rare ability to take character risk after character risk and have it work out -- for the most part. Few NFL teams rest more on their head coaches. And when you consider what the Bengals were before he showed up -- a franchise that couldn't manage a winning season from 1991 through 2001 -- Lewis' value becomes even more clear.