On the day Pete Carroll accepted the Seattle Seahawks’ offer to become their head coach for the 2010 season, he shared a conversation with his close friend Yogi Roth. Carroll had washed out of truncated, ineffective stints with the New York Jets and New England Patriots a decade prior. The Seattle job would be Carroll’s final chance, he knew, to test himself and either succeed or fail at the sport’s highest level.

Carroll’s nine-year reign at Southern California had made him one of the most successful coaches in America. In the minds of most NFL officials, fairly or not, he remained a gum-chewing, fist-pumping, mantra-spouting softie, perfectly enthusiastic for college kids but not disciplined enough for professionals. In college, he was king. In the NFL, he was nicknamed “Pom-Pom Pete.”

“What changes now?” Roth asked Carroll when they spoke.

“Nothing,” Carroll replied, to Roth’s recollection. “Nothing changes now. I’m not changing one thing other than which day of the week we play. If I’m going down, I’m going down my way.”

Carroll, 63, is at the top of his profession, on the cusp of one of the greatest coaching accomplishments in NFL history. Last year, he became the third head coach ever to win both a college national championship and a Super Bowl. On Sunday, with a win over the New England Patriots, Carroll can become the seventh to win consecutive Super Bowls. The list he would join? Vince Lombardi, Don Shula, Chuck Noll, Jimmy Johnson, Mike Shanahan and Bill Belichick. No one thinks Pete Carroll is a joke anymore.

Carroll can cement himself as one of the NFL’s all-time great coaches two decades after the Jets fired him after one season and 15 years after the Patriots dispatched him after three years. How did Carroll morph from an NFL flameout to perhaps its most dominant coach?

During his tenure at USC, Carroll never changed his views nor his philosophies. But he did learn how to better articulate them – both to himself and others – and instill them into his team. He decided what mattered most to him. He clarified his vision. In the years between missing the playoffs with the Patriots and taking over in Seattle, Carroll had discovered what, exactly, he meant by “his way.”

“I didn’t know him in New England,” said Jacksonville Jaguars Coach Gus Bradley, Carroll’s first defensive coordinator in Seattle. “I just know him as a man that has great convictions and great vision on what he wants to accomplish.”

Carroll’s excellence in Seattle grew from his experiences with the Jets and Patriots. The Jets hired Carroll in 1994, and in his very first team meeting he outlined his style, encouraging and enthusiastic. He sensed players appreciated his speech, and then he turned and saw the grim look on owner Leon Hess’s face. Hess, an old-school owner, expected fire and brimstone.

Carroll “knew he was in trouble right off the bat,” said Roth, a former player and assistant coach and the co-author of Carroll’s book, “Win Forever.”

Carroll started 6-5 with the Jets, but they lost their final five games. Hess stunned Carroll when he fired him after just one season and replaced him with Rich Kotite, who would be comically overmatched in New York. On the day the Jets switched coaches, the New York Post ran photos of Carroll and Kotite above the back-page headline, “Dumb And Dumber.”

Carroll’s prowess as a defensive coordinator earned him another chance, and the Patriots hired him in 1997 to replace Bill Parcells, who had bolted following a Super Bowl loss. Carroll went 10-6 with a playoff win in his first year and made the playoffs again with a 9-7 record the following year. But after he regressed again with an 8-8 record in his third season, Patriots owner Robert Kraft fired Carroll. (It worked out — Kraft replaced Carroll with Belichick and the Patriots won three Super Bowls following the 2001, ’03 and ’04 seasons.)

Roth calls the notion that Carroll failed in his first NFL head coaching roles “a misnomer.” He went 33-31 and made the playoffs twice in four seasons. But Carroll had also gained a damaging reputation as a too-nice “player’s coach,” his grinning zeal cutting against the NFL’s dour grain.

Carroll took a year off to evaluate himself and his career. He served as a consultant for teams, did charity work and wrote columns for Sports Illustrated’s web site. What had gone wrong in the NFL gnawed at him. He believed his ideas and his style would work, and he could not solve why they had not.

In the summer of 2000, Carroll was reading a book by legendary UCLA basketball coach John Wooden, which described the importance of a clear, detailed philosophy. Carroll shut the book and started writing. “I embarked on a process of discovering who I was, not only as a football coach, but more important, as a person,” Carroll writes in “Win Forever.” “At one point I leaned back in my chair, football in hand, and smiled.”

Carroll felt that in New England and New York, he had been undercut by owners and front offices that didn’t embrace him. Now he realized it had partially been his fault. He had never clearly explained his plan, mainly because he had never articulated it to himself. He recognized the difference between broad concepts and a clear plan.

“I think he was always himself,” Roth said. “I just don’t think he was as organized then as he is now. He would tell me, ‘I didn’t do a good enough job of telling them the vision that I had.’ I think he’s extremely at peace with it.”

And so Carroll jotted down his beliefs. He defined himself, first and foremost, as a competitor, and everything in his next football program would funnel back to competition. His players would play for one another and build “trust-based relationships.” He would prioritize practice. He would make sure his assistant coaches, Roth said, “brought a ridiculous amount of energy with purposeful language.”

Those were his principles, and he would not compromise. Carroll knew if he ever returned to the NFL, he needed everyone in the organization to buy into his plan. He required control of the roster, so he could weed out selfish players and find those willing to compete at the level he demanded.

For Carroll, USC served as a testing ground. Carroll held responsibility for every facet of the program, from recruiting to academics. He could – and did – take his players to a Manhattan Beach volleyball tournament for two hours in the afternoon before a key preseason scrimmage, an activity designed to teach them how to refocus between college parties and big games.

Carroll vowed he would return to the NFL only in a “perfect” situation, Roth said. His competitiveness made him eager to take another shot at the sport’s highest level, and several teams, including the Miami Dolphins, made overtures as USC became a juggernaut. But Carroll would only leap back into the NFL on his terms. In 2009, Seahawks CEO Tod Leiweke convinced Carroll he would have full autonomy and support.  “I’m in,” Carroll told him.

The Post Sports Live crew looks at Super Bowl XLIX's biggest storylines, from the Patriots' DeflateGate to the Seahawks' potential repeat. (Post Sports Live/The Washington Post)

“When this opportunity came here, it was expressed and clearly laid out that I could have the same kind of responsibility and the same kind of approach” as he did at USC, Carroll said this week at a press conference in Arizona. “So it’s been really instrumental, because the way we do things isn’t the way a lot of other people do things. And so we really needed our own way to do it.

“We needed our own language and our own control and our own decision-making process. I think it’s made all the difference in the world for us – not to talk about what was, but just what it is now. It’s what every coach needs, I think, to be at his best. The format and the structure that is generally accepted in the league is not that. We’ve set out to kind of show that this is the way organizations can be run.”

At practice, players must tap a sign and say “I’m in” before stepping on the field. Carroll holds “Competition Wednesdays” and “No Turnover Thursdays.” Carroll will sometimes remind his team that the definition of compete is “to strive against another,” but that the word derives from the Latin competere, which means “to strive together.”

He stokes competition by reviewing practice film daily and with games, like shooting baskets before practice. He allows individualism within the team, so Richard Sherman can cultivate a trash-talking, deep-thinking persona while Marshawn Lynch can stiff-arm any question reporters ask him with quit-bothering-me repetition.

“One of the things Pete really tries to do is allow us to have fun,” wide receiver Doug Baldwin said. “When we wake up in the morning, [we] enjoy coming to work. That allows us to go out there and play football and be free. Ultimately, it brings us closer together.”

Carroll has molded the Seahawks in the manner he envisioned years ago, when he put down Wooden’s book and started scribbling. They may be different, but they do things their way.

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