Is Ray Lewis the greatest gridiron leader ever?

The man in the black pullover, black pants and black skullcap crouched next to the visitors' bench at Qualcomm Stadium, his hands on his knees, his energy emanating everywhere. Just before the ball was snapped, he reached down, grabbed a bit of sideline chalk and rubbed it vigorously in his hands.

I couldn't tell if Ray Lewis was doing this for good luck, or as a means of trying to convince himself he was actually part of the action. Whatever the great linebacker's intent, his intensity was awe-inspiring.

As Baltimore Ravens receiver Tandon Doss took a short pass from Joe Flacco and slithered across midfield with three minutes left in overtime of a Nov. 25 game between the Ravens and San Diego Chargers, the 37-year-old Lewis still served as his team's emotional epicenter.

"That's a first down!" Lewis screamed as he sprung from his crouch and uncoiled his sculpted body, making the corresponding arm gesture for effect. "Let's go! Come on!"

A few minutes later, as rookie Justin Tucker's 38-yard field goal floated through the uprights to give the Ravens a somewhat stunning victory, Lewis charged off the field looking as triumphant and drained as the men who'd actually bled and sweat for the cause. He was, quite likely, the only NFL player who would have dared behave so boldly in such a context, and surely the only one who could actually get away with it.

I'd stood on the Ravens' sideline for the previous 45 minutes and watched Lewis, who Wednesday announced that he will retire following the Ravens' final postseason game, as the end of the fourth quarter and overtime period unfolded. Observing his passionate yet conflicted persona from such close quarters was truly mesmerizing.

I've covered the NFL for nearly a quarter century, and this was one of those indelible experiences I'll always treasure. I was just a few feet from Lewis, and though he and I know each other fairly well, we never made eye contact. He was too locked in, too determined to be there for his team, even as he crouched on the sideline while the players in cleats and helmets fought for a favorable outcome.

There are warriors, and there are leaders — and there are leaders among leaders. It's quite possible that Lewis, in addition to being the greatest defensive player of his generation, impacts the emotional states of those around him like no one who has ever donned a pair of shoulder pads.

[Related: Ray Lewis symbolizes NFL – not just Ravens | Photos]

Know this: When the Indianapolis Colts enter M&T Bank Stadium for Sunday's first-round playoff game in Baltimore — and Lewis suits up and plays for the first time since tearing his triceps in mid-October — they will encounter a psychotically supercharged Ravens team spurred by the return of the franchise's motivational catalyst.

In his first game back, in what could be his last game in Baltimore, or anywhere, Lewis is sure to have everyone in purple performing at a fever pitch.

"Leadership isn't given — it's earned," says former NFL fullback Lorenzo Neal, who became known for his leadership skills during a 17-year career that concluded with a 2008 stint in Baltimore. "Ray Lewis absolutely earned leadership, in a way that caused the coaches, staff members, teammates and everyone around him to say, 'Oh my God.' Ray Lewis would tell you to whip a bear with a switch, or that you could go fight Mike Tyson in his prime, and you'd believe it, because he worked harder than anyone, and more passionately."

It's important to understand that Lewis, for all his incredible accomplishments, didn't rely on natural talent to earn that leadership. Sure, he's a better athlete than most of us, but he's undersized for an inside linebacker, and even in his prime his speed was nowhere close to exceptional.

Because he ascended to the top of his profession on the strength of intangibles — work ethic, attention to detail, relentless passion, indefatigable drive — Lewis' locker-room cred is tremendous. I exist in a world in which players routinely take private jabs at one another, especially those whose outsized personalities cause them to become public caricatures. Yet I've never covered an athlete more revered by teammates and opponents than Lewis, who habitually exceeds the lofty expectations of the newcomers that enter the Baltimore locker room.

"Please, please try to capture all the [expletive] Ray embodies that has nothing to do with measurable athletic achievement or talent," says Tony Pashos, a Ravens tackle from 2003-06. "When he speaks to you, he has a charisma that just overtakes you. He was so demanding of us all. And I feel like he was on a different calling than even the Hall of Fame. He was possessed.

"Football is different than other sports. It's a lifestyle game. But dude, that guy? It was everything. It was like, 'There's nothing else on this planet except this arena.' It's almost like Ray was born inside 'Gladiator.' And I know he loved that movie."

Indeed, the cinematic Maximus and the smack-you-into-next-week linebacker share plenty of parallels, including a story arc filled with peaks, valleys and bloodshed. Lewis, of course, fought back from entanglement in a double homicide and a guilty plea for obstruction of justice to lead his team to a Super Bowl title and become a cherished figure in the Baltimore community known for his charitable endeavors and positive outlook.

To be sure, there’s a sincerity to Lewis’ message that resonates with everyone he encounters (just ask my daughter), even the most cynical among them.

"Bart [Scott, now with the Jets] used to make fun of him all the time," says former NFL defensive lineman Trevor Pryce, who played for the Ravens from 2006-10. "Ray would be giving one of those corny speeches on a Saturday night, and he and some of the older guys would say, 'Jesus, we all want to go to our room — please stop talking.'

"But there's a genuineness to it, and it works. And it really goes beyond the locker room. He had the city of Baltimore on his back. Before him, we had nothing. If you watched him these past few months, the fact that you can not be playing in a game and can be in the middle of the [pregame] huddle giving the speech? That's just crazy."

[More: Ray Lewis made Baltimore forget about Colts]

You want crazy? You know how numerous NFL coaches script plays before a game, or make up situation-specific tip sheets for their players? Well, Lewis is such a student of the game that he makes up such a sheet for his coaches. Even an esteemed strategist such as current Jets coach Rex Ryan enthusiastically accepted the veteran's advice on a regular basis.

"I've sat in his house with him and watched film for four or five hours at a time," Neal says. "He's an animal. And then, on Saturday nights, he'd walk up to Rex and hand him his 'call sheet,' which was a sheet of paper he'd draw up that listed which defenses he thought would work in which situations. To see Rex Ryan ask him for that sheet, and then implement it? A player respected enough to tell the coaches what to run? It was so amazing."

Film study has allowed Lewis to predict where opponents will go on a given play, which is one reason he tends to get to the right place so quickly. There's another one, however. With Lewis, the normal limitations of stamina do not apply.

"That [expletive] has a motor," Pryce says. "I've never seen anyone like him. That's why people think he's fast — because every play, he's running at full speed. He's not a world-class athlete. Even in his prime, there were defensive ends who ran faster than he did. But he runs at full speed 100 percent of the time.

"I don't understand it. It's the most bizarre things I've ever seen. He can sprint to one sideline, make a tackle, go back to the huddle and sprint all the way to the other sideline on the next play. I never saw him get tired. He's like a dog playing 'fetch.' He can play all day. There are 1,000 guys that are big, strong and fast. Some of them can't even play in the league. But none of them can run sideline-to-sideline at full speed for 70-something plays."

Seventeen seasons into an immortal career, and battling through the aftermath of a torn triceps, Lewis probably won't be Baltimore's biggest playmaker on Sunday, or, if the Ravens win, in any of their remaining playoff contests. However, if you think his role will simply be ceremonial, that his presence might actually be counter-productive, I think you're underestimating the man's prodigious motivational powers.

"Here's what happens with being such a badass: People start judging you against you," Pashos says. "Well, great — he's not what he once was. But you know what happens when Ray Lewis is in the locker room, and on the field? Guess what, you just maximized your entire salary cap, because everyone around him is playing at the highest level he can play.

"When I hear about the great ones like [Boston Celtics legend] Bill Russell, they say that he made everyone around him better. That's Ray. If you could wrap up all the qualities of all the Hall of Famers, he's got 'em all. And those five to 10 minutes in the locker room before we charged through that tunnel? I'm getting goosebumps even talking about it. It was like he bottled up everything that the sport embodies."

When Lewis gathered his teammates Wednesday and told him that these playoffs would be his "final ride," don't think it didn't galvanize that locker room in a way that those of us who haven't played with Lewis can't truly comprehend. About an hour after that speech, I got a text from Ravens defensive end/linebacker Terrell Suggs, the 2011 NFL defensive player of the year, who has fought back from a torn Achilles tendon and, more recently, a torn biceps to become an unlikely participant in Baltimore's drive for a second Super Bowl. It read, simply, "ON!!!!"

That's four exclamation points, on a keyboard, on a Wednesday. Multiply that energy by a zillion, and that's the Ravens' pregame huddle during Lewis' Are my dogs in the house? speech come Sunday afternoon.

The Colts have been riding their own wave of emotion in the wake of coach Chuck Pagano's return following treatment for leukemia, and they're going back to the city the franchise inhabited from 1953-84 before fleeing in the middle of the night. They're about to feel the power of a leader among leaders being honored by the teammates and fans who've come to venerate him, in the manner that he would most appreciate.

Brace yourself, men in the horseshoe-covered helmets. To borrow from Chris Cornell, Ray Lewis is not your autumn moon. He is the night.

[More: Teammates new and old react to Lewis' announcement]

"It's gonna be electrical," Pashos says. "They say winning and losing is contagious. Well, Ray is contagious. His greatness is contagious."

In this case, it may be transformative. To Pryce, who lives in nearby Columbia, Md., Lewis' announcement was a game-changer.

"There was no doubt in my mind the Colts were gonna win that game," he says. "Now? They don't stand a chance. The stadium is gonna be on fire. It's gonna be a mob scene. It's gonna be one of those things where you say, 'Wow.' It'll be like [an English] Premiership soccer game. It's gonna be insane.

"And it all starts with Ray."

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