More than two months after the Tampa Bay Buccaneers scorched the Oakland Raiders 48-21 in Super Bowl XXXVII, Jon Gruden gathered his team on a football field again for the first time.

"Forget about what happened last year," the head coach told his players during the April 8 workout. "It's over. It's done with."

It is a measure of Gruden's ability to lead that Warren Sapp, Ronde Barber, Anthony McFarland and Chartric Darby attended the workout even though they were recovering from offseason surgeries and couldn't participate in drills.

"This is as important a time of year as there is, really," Gruden said. "We need to see improvement in all players and coaches alike. We have to start over in terms of generating the camaraderie, the unity, the chemistry on this team."

Teams with new coaches

Check out Greg Garber's takes on the five new coaches: Jack Del Rio -- Jaguars Del Rio has the challenge of turning the Jags back into a winner. Dennis Erickson -- 49ers Erickson struck out in Seattle, but wants to prove that he can win in the NFL. Marvin Lewis -- Bengals The Bengals believe Lewis is the man to eventually end years of struggling and ineptness. Steve Mariucci -- Lions Mariucci has to turn around a Lions team that won just five games the past two seasons. Bill Parcells -- Cowboys Expect Parcells to struggle at first, but then succeed during his tenure with the Cowboys.

Admittedly, Gruden has an exceedingly low threshold of excitement -- in his mind, every time of year is important as there is, really -- but that's what allowed him to take an underachieving 9-7 team to a 12-4 record and the first Super Bowl win in franchise history in his first season in Tampa.

"Not only was Jon a great coach for us," said Gruden's boss, Tampa Bay general manager Rich McKay, "but he was a great fit, too. It shows how important that head coaching chemistry can be. We were problematic on offense, to say the least, and he obviously helped us there.

"He was a jolt compared to what we had come to know."

Gruden followed the departed Tony Dungy, who was 56-46 in six seasons with Tampa Bay and made the playoffs four times.

"When we hired Tony, he was a great fit at that time," McKay said. "He was a patient guy that was willing to let us draft and play a lot of young players, and we built the core of our team that way. So I've seen it from both sides."

Indeed, it was a double switch that worked well for both the Bucs and Indianapolis Colts, who went from 6-10 to 10-6 under Dungy and made the playoffs. While Gruden's fire and offensive expertise was just the thing for the mature, defense-driven Bucs, Dungy's defensive knowledge and cool, calm manner was just what the struggling Colts needed.

"Yes, there's always another way to skin a cat," said Colts president Bill Polian. "In our particular case, Tony's defense fit perfectly with the personnel we already had in place. While we had to add some players, and still do, we didn't have to cast a lot of players aside.

"The same thing was true in Tampa. They revamped their offense, but didn't have to cast anyone aside."

Clearly, a change in direction and philosophy from a new head coach can make a difference in the bottom-line item of victories. Of the six teams that made the biggest improvements, three were working under new head coaches.

After George Seifert lost two of every three games (16-32) for three seasons, the Carolina Panthers turned to Giants defensive coordinator John Fox. The team went 1-15 in 2001, to 7-9 last year, including winning four of the last five. That plus-six mark was the league's best, followed by the Buffalo Bills (plus-five), the Colts and Tennessee Titans (plus-four) and the Bucs and Giants (plus-3).

Fox's secret? He borrowed some of the anal-retentive habits of Giants' head coach Jim Fassel.

"Jim was very organized," Fox said. "A lot of his schedules, in-season and offseason and training camp, were things I decided to bring with me."

In five seasons with the Giants, Fox presided over a defense that shut out the Minnesota Vikings in the 2000 NFC championship game and helped Michael Strahan set an NFL record with 22.5 sacks a year later.

"I saw John after the season, and he said he always wondered what the heck it was I did (in the office) all night," Fassel said. "He said the team would all have their unit meetings, and he'd see me bouncing in and out of them. John said, 'Well, I quickly found out you were busier than hell.' "

Of the five new head coaches in the NFL this season, two of them -- Cincinnati's Marvin Lewis and Jacksonville's Jack Del Rio -- are rookies and discovering, just as Fox did, that the head coach's life is a little more complicated than the coordinator's. Leading an entire team, not just a unit of 20 or so players, requires an unusual set of skills.

As previous head coaches in the NFL, this is something that Bill Parcells (Dallas), Dennis Erickson (San Francisco) and Steve Mariucci (Detroit) already understood.

"It's one thing for me to lay out a plan, it's another for it to be implemented," explained Matt Millen, the Lions' president and CEO. "I'm not standing in front of the team every day. Steve is.

"I expect leadership ability and I expect the team to be led. But it's more than that. It's also leading your staff, being able to pull together the whole group. It's knowing what you want and where you want to go.

"I believe the most important part of the head coach's job is the inter-personal skills. Does he have good people skills? Can he make you take another step?"

Polian's description of Dungy's first days in Indianapolis underlines Millen's point.

"I was very certain that Tony would put his own stamp on the team in terms of how he approached every facet of the organization," Polian said. "He did that immediately. How he dealt with players, dealt with personnel issues, set up training camp. … He won the players over immediately because he's very straightforward, extremely objective and bright. They could see that immediately."

Means to an end
As an NFL linebacker for a dozen seasons, Millen had a broad and varied experience as far as head coaches went. There were Tom Flores and Mike Shanahan with the Raiders from 1980-88, George Seifert with the 49ers from 1989-90 and Joe Gibbs with the Redskins in 1991.

"I really like watching the different styles," Millen says. "Parcells has his way, Steve (Mariucci) has his. Mike Shanahan has a different approach. Watching Joe Torre with the Yankees, he has a successful method, too. The means may be different, but the ends aren't.

Successful NFL coaches -- successes in any walk of life, actually -- all seem to be supremely confident, uniformly intelligent and diligently organized. Look at the cover of a recent Sports Illustrated magazine with Parcells, whistle around his neck, sporting a tough Vince Lombardi-like look.

Parcells is the veteran of the five new head coaches this year; he's resurrected three franchises -- the Giants, Jets and Patriots. In all three cases, he did it by instilling a healthy respect -- some would call it fear and intimidation -- in his players. After surviving a 3-12-1 season in his first year with the Giants, 1983, he cleaned out all the bad actors and took his team to two Super Bowl victories.

	“	Slowly, the game evolved to the point, where every situation is a different personnel package. Down and distance change, so you have different people and packages. More is needed from a coach out there than ever before. It all goes back to the head coach being an even better manager and leader. ”
		—Lions GM Matt Millen

Already, his stamp is on the Cowboys, whose training room is virtually empty, compared to recent seasons under Dave Campo. Parcells is not afraid to tweak his players. Remember when he used the derogatory handle "she" to describe fragile Patriots receiver Terry Glenn?

Much attention has been focused on running back Troy Hambrick, the heir apparent to Emmitt Smith. Parcells spent much of the Cowboys' free agent budget on offensive linemen to block for Hambrick, but it hasn't stopped him from applying the needle. Early on, Parcells called him a "toe-dipper," which means he runs hard only when he sees a big opening.

"I'm waiting to see the ability to sustain a running attack over a consistent period of time," Parcells said. "He's got to show me he can go in this game and if it's 95 degrees down here, and he can play, and that he's got enough stamina, that he's not one of those backs that holds his hand up."

What about confidence?

"It's all about confidence," acknowledges Baltimore Ravens general manager Ozzie Newsome. "When I try to play golf they always tell me, 'You won't make the shot if you don't believe you're going to make it.'

"We were a very confident team in 2000 when we won the Super Bowl. Some people thought we were cocky. Brian (Billick) led that way. You saw it with Jon Gruden last year. Down in Tampa, they got into thinking that maybe they could only win with defense. He changed their thinking offensively. They started believing they could score points."

Polian agees. "The successful coaches succeed because they are able to convey that confidence to the players and the staff," he said.

According to Millen, the first person head coaches must learn to master is themselves.

"A head coach has to know who he is," Millen said. "It's no different than any other walk of life. The successful ones are the ones who know themselves. You stand in front of a group of men, young players, older coaches, you have to be believable.

Early in training camp, Mariucci said: "We have to develop some leaders here. It's all about establishing an air of professionalism in everything that we do, even down to the tiniest detail. There are going to be a lot of young guys on this team and we have to make sure they know what's expected of them."

The players say they are aware.

"There's a new vibe that's there and everyone can feel it," said linebacker Barrett Green early in training camp. "There's a different attitude, a different approach to how we're going to do things. I don't know how to explain it except to say that there's a growing confidence in the locker room and there's reason to be optimistic coming into this season."

An unwavering philosophy
While good head coaches develop an effective game plan, great ones are able to adjust their philosophies when circumstances dictate.

"I go back to (Bear) Bryant at Alabama," Newsome said. "He won with Joe Namath and Ken Stabler throwing the football. Then, when he couldn't get that kind of athlete, he went to the wishbone. His ability to adjust was the key. Don Shula won with (fullback Larry) Csonka and (halfback Jim) Kiick running the ball. Then he gets Dan Marino and starts throwing it all over the lot.

"Sometimes the ability to bring structure within change is what makes coaches successful."

In Cincinnati, Marvin Lewis has brought a new attention to detail -- something that was lacking.

	New Cowboys coach Bill Parcells will face every one of his former teams this season.

He took advantage of an NFL rule that allowed him to hold two extra mini-camps as a rookie head coach. After releasing 18 veteran players in his first five months on the job and hiring 10 new coaches, Lewis needed all the quality time with his team he could get.

Heading into training camp, the Bengals held the league maximum 30 on-field practices and coaching sessions. Eighteen came in the three, three-day mini-camps, in addition to 12 others. Those practices added up to about 1,000 practice snaps -- roughly an entire seasons' worth.

"We will have had almost two seasons of work by the time training camp is over," Lewis said.

The rookie head coach went out of his way to reach out to running back Corey Dillon -- one of only four running backs in history to clear 1,000 yards in each of his first six seasons.

"We are asking him to take over the leadership and assert himself as one of our best players and take the responsibility of that position," Lewis said. "He has to have something to go out and battle about each day to keep his spirit."

Said Dillon, "If that's what Coach Lewis wants, that's what Coach Lewis gets."

After noting that eight Jaguars players were on the injured reserve list at season's end -- two offensive linemen, Aaron Koch and Chris Ziemann, each suffered season-ending knee injuries in offseason non-contact drills -- Del Rio changed the team's approach to weight training.

Gone are most of the heavy free weights and the Olympic-style lifting techniques employed by Tom Coughlin. Del Rio favors weight-lifting machines over free weights and installed Mark Asanovich as the new strength and conditioning coach.

"We're not going to do anything that has a lot of orthopedic stress involved," Asanovich said. "Football players get a lot of orthopedic stress out on the field, so we're not going to compound that in the weight room."

In San Francisco, Dennis Erickson has already changed the training camp climate. Unlike the head coaches before him -- Bill Walsh, George Seifert and Steve Mariucci -- he believes in hitting, lots of it.

"It's hard to teach a guy to take on a block if he never takes one on," Erickson reasoned.

Millen argues that the role of head coach today is more important than it's ever been.

"Absolutely," he said. "The game has changed from days of Vince Lombardi and Don Shula and Tom Landry and Joe Gibbs. When we were coming through, the game was played on the field -- you were given a game plan and, heck, you called the stuff yourself.

"Slowly, the game evolved to the point, where every situation is a different personnel package. Down and distance change, so you have different people and packages. More is needed from a coach out there than ever before. It all goes back to the head coach being an even better manager and leader."

And that brings it back to Gruden, who hasn't slowed down one bit following Tampa Bay's Super Bowl championship.

The Tampa Bay offense was not exactly a juggernaut last season; with the best defense it wasn't really necessary. The Bucs' scored 346 points, averaging 21.6 per game. But in the playoffs, they averaged 35.3.

Wisely, Gruden did not make wholesale changes on offense in the run to the Super Bowl. Instead, he tweaked and quietly sold the players on his system. This year, the offense is more of a priority.

The first two preseason games yielded modest results -- 22 plays for the first offense, for 114 yards, six first downs and 10 points. And yet, Gruden said he was happy.

"When you look at the film, we are making some first downs and moving the football and using all five eligibles and changing the launching spot," he said, launching into his own persuasive pitch. "We're growing. We're optimistic. We feel we have the nucleus of a good offensive club.

Gruden then laid down the challenge that may help drive the Bucs to a rare repeat Super Bowl victory.

"Can we become great?" he asked. "That's our goal."

Greg Garber is a senior writer at ESPN.com.