In the NCAA Tournament, you had better have one.

To many, it's an article of faith, the main ingredient for success. You need a steady presence at the point, someone who can adjust quickly to unfamiliar opponents, temper his team's emotion in a do-or-die game and, of course, deliver in the clutch.

Duke's Jason Williams has been a versatile leader for the Blue Devils this season.(AP)

To others, that's just a "flaming myth," as one veteran observer of the game wrote in his newspaper column Monday.

This year's tournament features a number of outstanding point guards who are fully capable of providing the leadership necessary to make a sustained run. They include Duke's Jason Williams, Iowa State's Jamaal Tinsley, Florida's Brett Nelson, UCLA's Earl Watson and Boston College's Troy Bell, among others.

But are they going to be more important than their teammates in the tourney? Look to the national champion point guards themselves for an answer, and there's disagreement.

"I think it has very little to do with the point guard, per se," said Indiana Pacers coach Isiah Thomas, point guard for Indiana's 1981 national champions. "I just think it has everything to do with the team and chemistry and the matchups you get."

"All you need is a hot run," said Vancouver Grizzlies guard Mike Bibby, point guard for Arizona's 1997 national champions. "My freshman year, we didn't do that good in the Pac-10, but we hit a hot streak in the tournament and won it. That's all I think you need."

Then how do you explain some of the point guards, Bibby included, who were such a critical part of recent national championship teams?

There was the gritty Bobby Hurley of Duke, son of a coach, who knew how to control tempo and could stick the 3-pointer when necessary. He won titles in 1991 and 1992. There was Tyus Edney of UCLA, who at 5-feet-11, made the tournament his own before an injury kept him out of the Bruins' victory in the 1995 championship game.

And last year, there was Michigan State's Mateen Cleaves, who didn't have a sweet shooting stroke but did have an indomitable presence as a leader.

Some other guards, though not necessarily point guards, who were most outstanding players in the Final Four during the 1990s: North Carolina's Donald Williams (1993), Kentucky's Tony Delk (1996) and Kentucky's Jeff Sheppard (1998).

In 1999, Connecticut's Richard Hamilton was the most outstanding player, but point guard Khalid El-Amin hit a pair of clutch free throws and offered a defiant attitude that the Huskies took into their title game against a team some were calling the best ever.

"I think your guards are the most important part," said Iowa coach Steve Alford, point guard for Indiana's 1987 national champion. "I may be biased there, but I think that when you're going into a tournament setting and you're trying to win six straight, you better have people who can take care of the ball. You better have people who know how to distribute the ball.

"And when the game's on the line, you need guys who can beat you off the dribble and create for themselves and make foul shots. A lot of that rests with what the backcourt has to do."

What about the great centers? Couldn't they be considered the key to success in the tournament? With so many teams and so many tournaments, it isn't hard to make a case either way. Consider the college careers of the NBA's best players at those positions.

Allen Iverson never went to the Final Four. Neither did Tim Duncan.

Jason Kidd never went beyond the regional semifinals. Shaquille O'Neal never made it past the second round.

But whether or not a point guard is the key to success, the game has evolved away from great centers such as Bill Russell, Kareem Abdul-Jabbar and Bill Walton. In the early 1980s, Houston's Hakeem Olajuwon and Georgetown's Patrick Ewing dominated. But in 1985-86, after several years of experimentation, the NCAA introduced a 45-second shot clock. In 1993-94, the clock was reduced to 35 seconds. If a team insisted on pounding the ball inside, it had a limited amount of time to do so.

The 3-point shot, introduced in 1986-87, might have been designed in part to open up the lane. But it only added another element that a team needs to win, an element that often comes from the guards.

But television analyst Quinn Buckner, point guard on Indiana's 1976 national championship team, stressed there's a lot more to the position than shooting statistics.

"The essence of the point guard is leadership," Buckner said. "At tournament time, you see so many different teams, and they help you get organized. Your team will have energy. You have to keep them directed. That's the point guard's responsibility.

"When it gets to the tournament, you can make subtle adjustments with the point guard, because he can do it on the spot. He understands what's trying to be done."

Edney provided one of the most memorable moments in tournament history, stunning Missouri with an electrifying, coast-to-coast drive for a game-winning basket.

But to him, the point guard's importance isn't necessarily the ability to break down a defense. It's the same thing Buckner talked about.

"The most important thing is to be the general out there and calm everybody else down," said Edney, now with the Pacers. "That's very important at tournament time because it's such an exciting time and such high intensity. It's do-or-die time. You need somebody who can make sure everything is running smoothly."

Only two freshman point guards, Bibby and Utah's 5-foot-8 Wat Misaka in 1944, have led their teams to national titles.

But for every person who insists the point guard is critical, someone else can argue the opposite side. Consider an item Monday in the Arizona Daily Star by Greg Hansen, the columnist who called the guard theory a "flaming myth."

Hansen noted that guards Damon Stoudamire and Khalid Reeves lost a combined three out of four first-round games for the Wildcats from 1992 to 1995. He mentioned another first-round loss for Arizona, in 1999, when Oklahoma forward Eduardo Najera outplayed guard Jason Terry of the Wildcats.

"What you need is a player that seizes the moment," Hansen wrote.

"Carpe diem" for hoops.

That's the point -- if not necessarily the point guard -- in March Madness.