IN NEW YORK The way Rex Ryan has whipped up the New York Jets, everyone acts 15 years old. Fat assistant coaches stampede up and down the sideline, excited as wild young rhinoceroses. Jaded millionaire receivers sail around with their arms thrown open wide like kids imitating airplanes, pretending to fly. "The Flight Boys," they call themselves.

Whether or not the Jets can continue their improbable amusement ride, Ryan has already proved a point: It's possible to laugh and play football at the same time. A lot of NFL coaches won't admit it's possible to do both, at least not aloud. But with his underdog team in the AFC championship game against the Pittsburgh Steelers, Ryan is giggling like it's a schoolyard dare.

"It's a triple-chinstrap game," he booms. "A straight ahead, no-fair-dodging game."

He looks and acts like an overgrown kid who has eaten too many Fudgsicles, a bully on the playground. He flips the finger, gets fined by the league, and his players think he's the most fun ever. When he talks, his voice rises with zeal, his double chin flaps, and he bares a straight line of white teeth in a grin that's overbroad, as if he's ready to take another big bite out of something. Some accuse him of smack talk, but he denies it. "Just telling the truth like I always try to do," he says.

Don't mistake him; Ryan is excellent at the professional drudgery of coaching, the all-night staff meetings and schematics. "Outstanding coach, excellent tactician, great fundamentals," says former Baltimore Ravens coach Brian Billick, for whom Ryan worked from 1999 till 2008.

Few are more sophisticated strategists, as Ryan has proved in two short but stunningly successful seasons in which he has reenergized a franchise that hasn't been to a Super Bowl since Joe Namath in 1969. But he's no good at the blank technical jargon that passes for NFL conversation. "That coach-speak, that nonsense, he doesn't do that," defensive end Trevor Pryce says.

What Ryan is really good at is feeling - and getting others to feel, too. He excels at contagion. He has made adoring believers out of his players with a blunt, rampant emotionalism that he and his twin brother Rob, the defensive coordinator of the Dallas Cowboys, inherited from their father, Buddy Ryan, one of the most indelibly bellicose NFL coaches of the 1980s.

"You might not always like what they have to say, but you won't misunderstand them," Buddy says of his sons. "I think his players like that honesty. Players are the first ones to know if you're a phony."

One moment Rex Ryan delivers comedy, the next rousing speeches, and the next, savage profanity. "A lot of F-bombs," defensive linemen Shaun Ellis said. "We've kind of gotten immune to that."

One reason he uses such blue language, he tells his players, is to toughen hides.

"Skin like an armadillo!" Ryan bays.

All of which has the Jets playing like the most jacked-up, nakedly emotional team in the playoffs. Emotion, and Ryan's genius for summoning it with speechifying and canny manipulation, has been a crucial factor in their AFC run. Take the stirring cry he delivered in mid-December, on the eve of a regular season meeting with the Steelers. With the Jets on a two-game losing streak and in danger of missing the playoffs, Ryan had a blunt confrontation with his team. "When things go bad, we don't run from it," Ellis says.

At the hotel on the night before the game Ryan delivered a fierce, choked exhortation in which he described the desperate expedition of conquistador Hernan Cortes, who sailed off to conquer Mexico in 1519. Cortes was so determined not to retreat, Ryan said, that he ordered his men to set fire to their ships. "They burned their boats!" Ryan shouted.

The following day, when the Jets and Steelers were tied at 10 at halftime, they took up the chant. "Burn the boats," the Jets said. "Burn the boats." Final score: Jets, 22-17.

They knew it was juvenile. They knew it was worthy of a high school locker room. Burn the boats? Fine. "We still got to get back to the airport, though," Ellis notes, wryly. Yet they ate it up anyway, and have been using it ever since.

"Burn your boats," Ellis says. "Definitely. It means go out there and leave nothing behind. I'm not going to say this is war, but basically, just go out there and don't intend on coming back. Just leave it all on the field."

Similarly, Ryan made a "personal" grudge match out of a seemingly unwinnable playoff game against the superior New England Patriots and quarterback Tom Brady, who had embarrassed them in an early December game on Monday Night Football, 45-3. Ryan summoned ex-Jet Dennis Byrd, partially paralyzed in on-field incident in 1992, to deliver a tear jerking pregame address. "I would give anything for one more play," Byrd said. Ryan then produced the jersey that had been cut off him while he lay prone on the field.

Ryan also messed with the heads of the opposition. He insulted Brady for not studying and baited Patriots Coach Bill Belichick by pronouncing him the greatest coach in the game.

"I thought what he did against Belichick was brilliant," Billick said. "If they lose, [Belichick's] the best coach in football, and if they win, it's 'Hey we just beat the best coach in football.' "

By kickoff the Jets were sky-high. Meantime the Patriots were almost "devoid of emotion," Billick observed, because they had devoted so much energy to trying to ignore Ryan. Ryan then delivered a knockout punch of a game plan that stymied the top offense in the league and left Brady spinning in a 28-21 upset.

Can he do it one more time? If the Jets win Sunday, they will have defeated the Indianapolis Colts, Patriots and Steelers - teams that in the last decade have combined for six Super Bowl rings and five league MVPs - all on the road. It's perhaps the toughest path to the Super Bowl ever. Considering the prospect, Ryan grins, teeth big as piano keys. His big voice comes from deep in his gut. "I think we're just the men for the job," he says.

But if so, it will be because Ryan reached down and once again found the boy in all of them, with his childish and grand improvisations. "I want that green-and-white confetti coming down," he says. "We want to hold the trophy. . . . We want that to be ours. We want the hat. We want the T-shirts."

A father's influence

Ryan's own boyhood was a succession of moves and brawls, as he followed his father around the league. Buddy Ryan was at once an innovator and a pugnacious old schooler, a Korean War master-sergeant who devised new defenses based on the primitive idea that the more you hit people, the better. A nomadic, feuding career took him to the Jets, the Vikings, the Bears, the Eagles, the Oilers and the Cardinals, before he retired 15 years ago to work a horse farm in Kentucky, where this week he answered the phone with a gruff, "Whacha got?"

By the time the Ryan boys reached high school age, they were so strapping and truculent it was difficult to control them. Buddy and their mother Doris divorced in 1966, and they were living in Toronto, cutting school and fighting. "She was having trouble keeping them straight," Buddy says. In 1976, after they got kicked off their football team for their tempers, Buddy brought them to Minnesota to live with him and his second wife, Joanie, full time. "I think they needed a firm hand," Buddy says.

Buddy put them to work as ball boys for the Vikings. He began to notice that when head coach Bud Grant talked, they listened. "They were observing when the other boys were playing," he says. "They were paying attention to what was going on."

When he shipped them off to college at Southwestern Oklahoma State, he urged them to study hotel management and food services; he didn't want them in the coaching grind. But each insisted, "Dad, I want to coach."

They begged him to show them the attacking defenses he was renowned for. So Buddy took them to a hotel in Weatherford, Okla., checked into a room, and set up an easel. He conducted a private clinic, "Went over the whole package." He found he didn't have much to teach them. "I was surprised at what they already knew," he said.

Buddy insisted they start at the dirt-ground level, and made a couple of calls. He placed Rex as a graduate assistant at division I-AA Eastern Kentucky under Roy Kidd, a renowned taskmaster who won 16 Ohio Valley Conference titles, and woke his players for 6 a.m. runs. Rex worked for nothing. Buddy says, "He did his ABCs."

If Buddy thought a taste of the grind would cure Rex, he was wrong. Rex loved it, the whole life. He got so excited calling blitzes, he would punch other staffers in the arm.

"Everything's a competition to him," says Keith Kidd, Roy's son, who is director of pro personnel for the Denver Broncos. "Coaches' kids are different . . . you live and die every Saturday, and you're so emotionally attached to it, because you learn the whole way of life, from the equipment trainers all the way up."

Ryan was an incurable gamer - so much so, that even on the morning of Keith's wedding, he dragged him outside for a game of Wiffle ball. The rest of the wedding party looked out the window in amazement at Ryan capering on the back lawn with a plastic bat and a little white ball.

Ryan wended his way to Division II New Mexico Highlands, then Morehead State, Cincinnati, Oklahoma and Kansas State. He finally got his big NFL break in 1999, when Billick heard him speak at a coaching clinic. Billick, like everyone, was carried away by his gusto.

Ryan was just a warmup act, and there were only a few people in the lecture hall to hear him. But he stood at the podium roaring and gesturing with fervor.

"There were about 10 people there, and you would have thought there were 100,000," Billick says. "He was clinic-ing up. He was passionate, knowledgeable. And I thought right then and there, boy, this is a guy you want on your staff."

They were the same qualities that the Jets would eventually find so irresistible. Ryan's secret, Billick maintains, is his infectiousness.

"The players pick up on it," Bilick says. "You have to match his energy, and passion, and verve for the game."

'Old guys and castaways'

There are a lot of high-passion players in the Jets' locker room, just waiting to match Ryan's. He brought them in for that very reason. He wanted guys with chips and resentments, such as LaDainian Tomlinson, the former league MVP running back who seemed washed up and was let go by the San Diego Chargers last winter, or Pryce, the 14th-year veteran former Pro Bowler, released in September by the Ravens.

"This team is built up of big offensive linemen, and old guys and castaways, you know what I mean?" Pryce says. "That's what unifies us: We have guys no one else wants. . . . He has in mind what a football team is supposed to be, what kind of parts and pieces and personalities he wants."

Not everyone wanted Ryan, either. Part of his connection to his players is based on the fact that he is a rejected vet, too, passed over by the Miami Dolphins, Atlanta Falcons, San Diego Chargers and Ravens for head jobs, before the Jets hired him in 2009 at the age of 46. By the time he got a chance to run his own team, he knew exactly the type of guy he wanted: high-octane soreheads. He has turned over fully half the Jets' roster in two seasons.

"All I can do is coach football, I'm not an expert on anything other than this game of football," Ryan says. "And I know the type of men it takes to play this game. I know what you look for in a guy."

According to Pryce, Ryan keeps a virtual "Rolodex" of playmakers who have bested him on the field.

"He wants people who beat up on him," Pryce says. "I think the thing about Rex's organization is that if you made an impression on him, he gives you a chance no matter what."

That was the case with Santonio Holmes, the former Super Bowl MVP the Steelers traded to the Jets last April for just a fifth-round draft choice, because of off-the-field issues that included a marijuana bust and disorderly conduct. Ryan was on the phone in his office when he got a message from General Manager Mike Tannenbaum: "Give a thumbs up if you want Santonio Holmes, or a thumbs down if you don't."

Ryan slammed down the phone, and he shouted: "What? Santonio Holmes?" He went pounding upstairs and told Tannenbaum, "Absolutely." Three times in one season, Holmes had burned Ryan's defenses for losses.

"I just knew that anybody that beat me that bad, that I'd just as soon have him on our team," he says.

Somehow, Ryan has forged a unit out of a potentially unmanageable bunch. His garrulousness obscures a subtle but superb talent for team building. He has melded all sorts of types, from aging retreads to outspoken stars such as cornerback Antonio Cromartie, who last week called Brady a human orifice. "He's the ultimate uniter," says Kidd. Ryan clearly likes having all those large, different personalities in the room.

"There is nobody alike," Ryan says, "Everybody is different, but that's the beauty of a locker room, is when you can respect everybody. Everybody is different. Every single person, different religious beliefs, the way they look, fat guys, good-looking guys or ugly guys. Everybody comes together and they have one goal."

It's a delicate balance, however, and at times, Ryan's emotive, free-speaking style has threatened to tip over into undisiciplined. During the Pro Bowl in Miami, Ryan gave the finger to a raucous crowd, and told fans to "Go [expletive] yourself." Wide receiver Braylon Edwards was arrested for drunk driving, and the team was fined $100,000 after strength coach Sal Alosi tripped a Miami Dolphin on a punt return.

"The things you're applauded for are the exact same things they'll run you out of town for," Billick notes. "Rex at top of his game is a players' coach. Players love him, he's outspoken. But when you hit that tough spot - and you always do - then you've lost control, you're arrogant, you're boastful."

But for the time being, Ryan's team is playing like a highly disciplined organization. Their loyalty to each other is palpable, and they say it starts with Ryan, who takes all blame when they lose and deflects credit when they win. After they beat the Patriots, he said, "It has nothing to do with me." To which Pryce replied affectionately with his own expletive: "Bull. It had everything to do with him."

Then there is the masterly job Ryan has done with second-year quarterback Mark Sanchez, guiding a loose kid to imminent superstardom and four playoff victories. Sanchez might have driven some coaches crazy. He exudes a surfer boy carefree-ness, with wings of curling hair, Skechers on his feet, and rope bracelets on his wrist. But Ryan has let him be himself.

Sanchez's relationship with Ryan was defined by an early encounter, when Sanchez was a draftee out of Southern California. He went to dinner with Ryan, owner Woody Johnson and several assistant coaches, and after the meal as they left the restaurant a jokey Sanchez decided to alarm his new bosses. There was a motorcycle parked at the curb, and Sanchez pretended it was his. He said, "All right, I'll see you guys later," swung a leg over the bike. "I was just messing around," he says. Some coaches would have gasped. Ryan laughed. He liked it.

Later, when Sanchez struggled with mistakes on the field and doubted himself, Ryan brought up the episode: "Be that guy that got on the motorcycle," he told Sanchez. "Just be him."

"Even in the toughest situations, he's always told me he's never wavered in his confidence," Sanchez says. "And it's taught me to never waver. You've got to trust yourself. When all else fails, get back to basics, go with what you know and trust your instincts. He'll always tell me in the toughest situations, 'Be yourself. Be the guy we drafted.' "

There is no tougher situation than the one the Jets now face. Ryan will try to summon another big swell of emotion in order to win in the cold, hostile environs of Pittsburgh's Heinz Field. It will be their third straight road game as underdog, and the question is whether their emotion is sustainable.

Moreover, the Jets will need serious substance to beat the ferociously physical Steelers, who have won two Super Bowls since the 2005 season and six trophies overall. If it's a matter of the Jets' inspiration against the Steelers' heavy hitting and hardware, it won't be enough. Ryan is cognizant of that, which is why he kept his incendiary talk to a minimum. But on Friday, Ryan pronounced his team ready, and with a confident verbal flourish suggested his team is ready for the playground again.

"They've had six Super Bowl trophies," he said. "If they want to put them on the field, we will play them, too."