The 10 of them met for dinner two years ago at the NFL combine in Indianapolis, an impromptu gathering during a week of February drudgery. In a private room, the members of the 1999 Philadelphia Eagles coaching staff swapped stories about working under head coach Andy Reid: late nights, career lessons and epic steakhouse dinners when Reid would order every appetizer — and then every dessert — on the menu.

At the end, the nine former assistants huddled around Reid for a picture. Of the nine coaches standing, seven of them had been NFL head coaches. They all owed something to the man who remained seated. The night had started as a reunion, became a roast and concluded as a tribute.

“We paid homage to Coach,” said Carolina Panthers Coach Ron Rivera, who started as a linebackers coach under Reid. “We really did, because he’s been such an influence on all of us.”

On Sunday night, Reid will take his 5-0 Kansas City Chiefs into Gillette Stadium for a showdown against Bill Belichick and the New England Patriots. The two coaches have defined their era, with obvious domination in Belichick’s case and with subtle impact in Reid’s. Belichick is the greatest coach in modern football. Reid may be the most important.

In his 20th season as a head coach, Reid, 60, has become one of the most influential figures in the NFL. Seven former assistants are current head coaches, including reigning Super Bowl champion Doug Pederson of the Philadelphia Eagles. That means a quarter of the league’s franchises are coached by Reid or somebody who learned under him.

A greater share have been shaped in some way by his offensive outlook. Reid is an acolyte of Mike Holmgren, who learned the West Coast offense from Bill Walsh. As that style predominated, few ran it better than Reid. But he has also been at the vanguard of how the NFL is changing, seeking new concepts from the college game, implementing them into his system and, along the way, reshaping offensive football.

And still, in popular opinion, Reid stands a rung below the all-time greats. Only four — Don Shula, Tom Landry, Belichick and Paul Brown — have been to the playoffs more than Reid. Just eight have won more regular season games, but Reid has never claimed the league’s ultimate prize.

“People can say what they want about head coaches and Super Bowl trophies,” former Reid assistant Steve Spagnuolo said. “We know it’s all about trophies. But there’s not a better head football coach/CEO in this league than Andy Reid. Had we won in ‘04, you’d be talking about Andy Reid and Bill Belichick in the same breath. The only difference is Super Bowls. Now, it’s a big difference.”

Perhaps his last best chance

This season may be Reid’s best chance to erase the worst parts of his reputation, to lessen the gap between him and Belichick, to win an elusive Super Bowl. Quarterback Patrick Mahomes, the rocket-armed quarterback for whom Kansas City traded up to pick in last year’s draft, has become an ideal centerpiece in Reid’s innovative attack and an MVP candidate. The Chiefs started last season 5-0, too, but if Mahomes can be the upgrade over Alex Smith that he seems to be, Reid may finally fill the lone hole in his career.

Belichick has coached in eight Super Bowls and won five. Reid has an 11-13 career playoff record and lost the only Super Bowl he reached — to Belichick, by three points, after the 2004 season. In popular perception, Belichick is a hoodie-clad savant with a grim visage, and Reid is a clock-botching doofus with a walrus mustache.

While Belichick has collected rings and accolades, Reid may claim a more profound impact and legacy. Two former assistants from his coaching tree (Pederson and John Harbaugh) have won Super Bowls as head coaches, and another (Rivera) coached in one. With his years-long experimentation and sudden overhaul of the West Coast offense, Reid has shaped modern NFL offense perhaps more than any other coach.

Belichick will leave a narrow mark beyond his own individual greatness. The eight NFL head coaches he produced have failed with staggering uniformity and depth. They have combined for a 160-233 regular season record (.407), no Super Bowl appearances and only one playoff victory, which came after the 2016 season when Bill O’Brien’s Houston Texans beat an Oakland Raiders team forced into starting a third-string rookie quarterback. Those Texans lost the next week — to Belichick’s Patriots.

Reid’s coaching tree has grown so expansive for several reasons. First, he identifies coaching talent well. Coaches who worked under Reid say his meticulous organization and work ethic rub off.

“I can rarely remember a time when I didn’t drive in and his car wasn’t there already, or drive out and his car had left,” said Brad Childress, a former Reid offensive coordinator who became the Minnesota Vikings' head coach.

A few months after Rivera started working for him, Reid called Rivera into his office and recommended he read Walsh’s “Finding the Winning Edge,” considered a bible among coaches. Rivera dove in and realized Reid had borrowed many of the book’s teachings, particularly about how to schedule. Today, Rivera uses the lessons to map out Carolina’s entire year, from minicamp practices to when coaches get vacation.

Harbaugh, the Baltimore Ravens coach, handled special teams under Reid for years in Philadelphia. When Harbaugh would visit Reid in his office, he noticed a message written on a three-by-five card behind Reid’s desk. It read: “Don’t Judge.” Harbaugh never asked Reid about it, but it stuck with him each time he saw it, and he understood the importance.

“The point of the whole thing was, as a coach, you don’t bring all your stuff into the thing,” Harbaugh said. “Take people for who they are and for where they’re at in their life — as football players, as coaches, whatever — and let them be who they are. Help them along the way where you can. Give them good advice.”

Rivera said Reid empowered assistants, giving them opportunities that would help prepare them to be a head coach. He said Reid cherishes the coaching tree he has created.

“All of us took meticulous notes so as not to miss anything that he was doing or sharing or expressing in hopes we could use it someday for ourselves,” said Spagnuolo, who went on to coach the St. Louis Rams. “It didn’t take too long to figure out this man was born to coach football.”

Staying current

As Reid built a perennial contender around quarterback Donovan McNabb in Philadelphia, taking the Eagles to four consecutive NFC title games, he constantly sought innovation. He gave assistants research projects on, say, the best teams at running screen passes or red zone plays. He wanted to stay current and looked anywhere to ensure he was.

When the Eagles drafted Kevin Kolb out of Houston in 2007, Reid studied the offense Kolb ran under then-coach Art Briles, one of the earliest adopters of run-pass options, even if the term “RPO” had yet to be coined. Even back then, Reid started blending the concept into his West Coast scheme.

“These colleges and high schools have been doing it a lot longer than what we have,” Reid said this week during a conference call with reporters. “So we’ve just kind of grown with it, and these kids know how to do that.”

In 2012, Reid went 4-12 and got fired by the Eagles. The experience accelerated his desire to update his offense, to ensure he remained ahead of how rules changes and college offenses had affected the NFL.

“He saw that there was a change in our sport, especially offensively,” Spagnuolo said. “And he made sure he brought in an influx of youth so that he could stay up with that. I think you’re seeing that now. He was always good at creating formational stress on the defense and mismatches, but I just think he’s taken it to a whole new level.”

When Reid acquired Smith to be his quarterback in Kansas City, he and then-quarterbacks coach Matt Nagy studied decade-old film of Smith at Utah, where he played for Urban Meyer. They realized the zone-read plays, jet sweeps and run-pass options would not only suit Smith but also fit into where the league was headed.

The West Coast offense is built on getting the ball to fast players with space around them, using balance between runs and passes to create that space. Reid’s new offensive system accomplishes the same objectives, but in wholly different fashion.

“I don’t know if Bill Walsh would recognize this offense anymore,” said Steve Mariucci, who coached with Reid in Green Bay and now is an NFL Network analyst. “Andy loves being the mad scientist.”

“In a never-ending battle to find unique ways to score points, I think he’s really kind of invented his own offense right now,” said Childress, now a head coach in the new Alliance of American Football.

In many ways, Reid is a link between the way NFL teams played offense for nearly three decades and the way they’ll play it in the future.

“He’s over the course of time been able to modify some of the traditional West Coast principles,” Belichick said this week. “The RPO certainly fits into that category, but he’s done a great job incorporating that, probably as much as any team we’ve seen — probably more than any team we’ve seen.”

‘On the cutting edge’

Already, Reid’s strategic influence has spread around the league. Reid and Nagy overhauled their offense to fit Smith’s strengths, and now Nagy is implementing those concepts in Chicago. Pederson won a Super Bowl in Philadelphia, and his offensive coordinator, Frank Reich, took his scheme to Indianapolis.

Reid’s impact is not limited to coaches who worked under him. Last year, Childress worked for the Chiefs as an offensive analyst, which included studying other teams. Sometimes, when watching the Los Angeles Rams, he would spot one of the Chiefs' plays. Childress would text Rams Coach Sean McVay, “Hmmm, seems like I saw that before.” McVay would jokingly acknowledge the theft, a common practice that signifies respect among coaches.

“[Reid] is on the cutting edge of offensive football year after year with different offensive coordinators, and they go out and they do the same thing around the league,” Harbaugh said. “So he’s the top coach in football, in that sense.”

In another sense, the one coaches crave most, Reid has never been the top coach in football. That may finally change this season, but it’s far from assured, or even probable. Whether the Chiefs win or not matters, but it can’t change how Reid shaped his sport. Reid may or may not be remembered as a Super Bowl champion, but he will be remembered.

“All of us want to leave a legacy,” Spagnuolo said. “You want to see positive outcomes for people you care for. And Andy has done that.”

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