“We came here and have done exactly to the letter what we did [at USC], in our approach and our thinking and everything,” said Seattle Coach Pete Carroll, whose enthusiastic style has taken hold throughout the Seahawks’ organization. (John Froschauer/Associated Press)

Pete Carroll took on a tough assignment in replacing Bill Parcells as head coach of the New England Patriots. He won 10 games, then nine the next year and eight in Year Three. It’s no wonder on his last day leading the franchise, a fan in the stands held up a sign that said, “Had the Tuna, but ended up with a Flounder.”

Carroll addressed reporters that day in January 2000, saying: “I’m real disappointed and forever will be.” Then, at 49 years of age, he set out to not just better understand himself, but to figure out why he was coaching and how he could be more effective.

In the years that followed, when Carroll took the reins at USC, parallel legacies began to emerge: Carroll was one of the most successful leaders the college game knew, and Carroll had been a complete flop as an NFL coach. In April 2008, in fact, the NFL Network debuted “NFL Top 10: Coaches Who Belonged in College.” Carroll was No. 9.

Now 61, Carroll is re-writing his NFL story. The Seahawks’ 11-5 record this season marks his best in the NFL and for the fourth time in seven seasons as a pro coach, Carroll is in the playoffs. He’s trying to become the first coach to jump from college to the NFL and win a Super Bowl since Barry Switzer in 1996. Between then and now, there has been a long list of college-to-pro failures, from Steve Spurrier to Nick Saban to Bobby Petrino.

When Carroll guides the Seahawks into FedEx Field on Sunday to face the Washington Redskins in a much-anticipated playoff game, it will mark a culmination of sorts. He turned around a listless franchise. He did it his way. Apparently, he can coach in the NFL.

The Post Sports Live crew offers up their Super Bowl predictions on the eve of the NFL postseason. (The Washington Post)

He did it with the same formula he’d used to win more than 80 percent of his games at USC (plus a national championship, later vacated).

“We came here and have done exactly to the letter what we did there,” he said this week, “in our approach and our thinking and everything.”

Carroll is one of the most colorful characters in the coaching ranks. He’s the second-oldest coach in the NFL, but as Seattle tight end Anthony McCoy says, “he acts like he’s the youngest.” Carroll is introspective and motivational. He has a reputation as a rah-rah guy, but he’s also calm and thoughtful. He works with a high-performance psychologist who has measured Carroll’s “neuroagility” — the ability to hop from topic to topic, intently focusing on each — as off-the-charts. He thinks football is more than a game, and coaching players is more than drawing up Xs and Os.

Carroll understood some of this when he was elevated from defensive coordinator to head coach of the New York Jets in 1994. He knew he wanted to be a head coach; he just didn’t know what that meant.

“I hadn’t thought about it really,” he said. “I just said okay, I’ll go for it.”

That team won just six games and closed the season with a five-game losing streak. Carroll was canned after one season. In the week that followed, he was offered defensive coordinator positions with the San Francisco 49ers and the Denver Broncos, coached at the time by Mike Shanahan.

“I thought I was going with Mike,” Carroll said. “I was really thrilled, after getting bounced with the Jets, that somebody called. I was on my way to the airport going to Denver, and I got a call in the car from Coach George Seifert.”

The Post Sports Live crew examines the 11-5 Seattle Seahawks, who are riding an impressive 5-game winning streak during which their average margin of victory is more than 26 points per game. (The Washington Post)

Carroll took the 49ers job and after two seasons was a head coach again, this time with the Patriots. But New England got worse each season and in January 2000, Patriots owner Bob Kraft decided the organization was headed in the wrong direction. Carroll needed a new direction, as well.

With the Jets, he struggled to articulate a philosophy and with the Patriots he had a difficult time instilling one. Unsure what he’d do next, Carroll took a year off from coaching, intent on crystallizing his methods and motivation. He became inspired reading legendary UCLA basketball coach John Wooden’s writings, and crafted his “Win Forever” model. Carroll spent the fall of 2000 scribbling notes, trying to make sense out of his values and vision, an entire philosophy centered around the idea of constantly competing.

“If you want to win forever, always compete,” is the Carroll mantra.

Carroll found quick success at USC and was confident his organizational philosophy would work in the NFL. But he didn’t feel like he’d ever get a chance to find out. No pro team, he figured, would give him the freedom to run an NFL franchise the way he ran USC.

“I was always anxious to see if we could do what we had developed — our approach and mentality and the way we cared for people and the way we looked after players and evaluated talent and all those things. I wanted to see if it would fit on the greatest stage on the highest level of competition,” he said.

The NFL became curious, too. The Seahawks fired Jim Mora after just one season and within a day had agreed to terms with Carroll, despite his previous struggles in the pro ranks.

“No one felt it was a huge leap of faith,” said one person familiar with the hiring process, who requested anonymity because he wasn’t authorized to talk about Carroll. “We just really noticed, man, this guy is hungry.”

Selling himself wasn’t difficult. Carroll believed in his philosophy and was in the process of writing a book about it. Yogi Roth, who’d spent four seasons on the USC coaching staff, was helping write “Win Forever,” and he was with the head coach when Carroll accepted the Seahawks job.

“I remember asking him, ‘How much do you think you’ll have to change?’ ” Roth recalled. “He said, ‘Not a drop. I’m not going to change anything I do.’ ”

Within the month, Carroll assembled everyone in the organization, about 300 in all, half in a conference room and about the same number watching the session streamed live — from coaches to scouts to the sales and marketing teams. The new head coach outlined his philosophy, the one he used at USC, the one he hoped would translate to the NFL.

It was a good first impression. Carroll’s philosophy and energy, team employees say, has infected every corner of the organization in the past three years. “He’s not just a football coach. He’s an inherent leader,” one person said. “If he was a CEO, he’d be a heck of a CEO. He has all the right stuff. He connects with everyone, looks people in the eye, he cares, he can see things quickly.”

The basic tenets are visible every single day throughout the team facility. The coach’s weekly script doesn’t emphasize the Redskins or containing quarterback Robert Griffin III. Wednesday is called “Competition Wednesday.” It is followed by “Turnover Thursday,” “No Repeat Friday,” “Review Saturday,” and “Game Day Sunday.” Finally, regardless of a win or loss in Washington this weekend, there will be “Tell the Truth Monday.”

On Sunday, that truth will be known. The Seahawks will try to continue their run through the NFC. And Carroll will continue to re-write his legacy as an NFL head coach.

“I’ve been in it long enough that I’m more stubborn about doing things exactly the way we want to do it,” he said. “I think we have a real good sense for consistency around here, and I think that’s just by appreciating the style and the way and the philosophy in how we do things, and not listening to people telling us that we can’t do it the way we want to do it.”