NORMAN, Okla. -- Asked to name his boss' worst vice, Steve Henson scrunches his face and scratches his head, looking as if he's trying to translate Sanskrit or understand the tax code. He and Lon Kruger go back more than 25 years, all the way to Henson's high school days in McPherson, Kansas, when Kruger recruited him to play at Kansas State.

He has stood beside Kruger on the sidelines in Illinois, UNLV, for the Atlanta Hawks and now Oklahoma; Henson knows the man about as well as he knows anyone. Henson can tell you how Kruger thinks, what he values and his athletic pedigree.

But a vice?

"Wow, I don't know," Henson says with a protracted sigh before finally settling on an answer. "I know. Ice cream. Yeah, definitely ice cream. He eats his ice cream on a regular basis."

Pressed to name Kruger's favorite flavor, Henson laughs out loud before answering.

Unlike most coaches at high-profile programs, Kruger has an open-door policy at Sooners practices. AP Photo/Sue Ogrocki

"Oh well, probably vanilla," Henson says.

What, you were expecting Rocky Road?

No, not out of Kruger, the most unassuming, polite, positive and yes, vanilla man in college basketball.

He is the very antithesis of the shills most folks imagine when they envision coaches, a bespectacled Everyman who loves his tractor and despises self-promotion with equal fervor.

"He's just so nice," Kansas coach Bill Self says, emphasizing the last word with wonder.

In an impressive career that includes NCAA tournament wins with a record five schools, five Sweet 16 appearances and one Final Four, Kruger remains one rung short of basketball heaven. He has never won a national championship.

But paired with a player who is the Abbott to his Costello, an effervescent bubble of a Bahamian named Buddy, Kruger has the best chance to rewrite the tired cliché.

A nice guy just might finish first.

It is the day before arguably the biggest basketball game at Oklahoma since Blake Griffin owned the campus. A month after their triple-overtime thriller, the Sooners and Jayhawks will battle again with nothing less than the Big 12 title on the line. ESPN's College GameDay crew is in Norman and the usually football-mad fandom has already gobbled up every seat in the Lloyd Noble Center.

As OU goes through its last practice before the game, a crush of sorority girls come into the gym and sit behind the scorers' table. Opposite them, a team of elementary-aged boys settles in a lower-bowl row. Behind the nets, two moms and their boys watch, iPhones at the ready to take pictures, and scattered throughout the gym are a handful of retirees, eyeing the Sooners intently.

When Kruger whistles the end of practice, the spectators all flood the court, the girls taking selfies with the players, the boys asking for autographs, the retirees asking questions.

"It looks like a mixer," jokes sports information director Mitch Heckart. The gaggle of girls is a new twist, but otherwise, this is pretty normal for Oklahoma.

Sooners' practices, either in the main gym or the more intimate practice arena, are open to anyone and everyone who would like to attend -- every single day of the season. Heckart can only remember Kruger closing practice when NCAA rules mandated the veil of secrecy during the NCAA tournament.

Otherwise, it's a come one, come all free ticket to practice.

Just as it was at Kansas State, Florida, Illinois and UNLV.

"He was pretty much an open book," says Joel Glass, Kruger's sports information director from his Florida days. "Nothing was ever closed."

That's not normal. Coaches might open the doors to invite-only guests but a free-for-all? No. They're too paranoid about protecting their secret inbounds plays and more, about protecting themselves.

There is a reason why managers create an impenetrable force field around most in-game huddles -- so the people sitting behind the team benches don't hear a head coach dog cussing his players.

Kruger doesn't dog cuss. He doesn't even scream. If he has something to say, he'll call his team over in a tight circle and practically whisper.

He mostly claps ferociously and talks endlessly, a stream of positive encouragement that sounds more like it belongs on a baseball diamond than a basketball court.

"Be quick, be quick, be quick," he says at one point.

"Good job, good job, good job" is another favorite, both said in a staccato voice usually reserved for catchers squatting behind home plate.

That's not coincidental.

Led by Buddy Hield, Lon Kruger has the talent to capture his first national championship as a head coach. AP Photo/Sue Ogrocki

The nicest guy in college basketball, the one most folks would walk past and think at best is a nerd and at worst a total wonk, might also be the most gifted athlete. The two-time Big 8 player of the year while at Kansas State, Kruger was drafted in 1974 by the Atlanta Hawks and the St. Louis Cardinals, and invited to the Dallas Cowboys rookie camp that same year.

He's also a scratch golfer.

"I mean he was a stud," Self says.

That athletic background makes Kruger wildly competitive -- he and Henson once spent more than three hours and two sock changes locked in a shooting contest -- but even that is tempered by his genuine decency.

Mike Shepherd first worked for Kruger as a student manager at Kansas State. Since then, he, like Henson, has followed his boss from one outpost to the next, coaching alongside Kruger at his alma mater, Florida and Illinois. Now the director of operations at Oklahoma, he ranks as one of Kruger's closest friends. The joke around the program is if Coach is thinking it, Shep has already done it.

Shepherd has seen Kruger at his beginnings and at his best, watched as he essentially remade himself from a tight-fisted, low-scoring, tempo-control freak to the freewheeling engineer of Buddy Ball. (According to Ken Pomeroy, UNLV's adjusted tempo in Kruger's last season ranked 110th, and that was from a low of 235; this season, the Sooners are 88th and last year ranked 17th). While his coaching philosophy has changed, Kruger hasn't.

The same thing that drove Kruger nuts at Kansas State gets his goat today. It's not foolish mistakes or a lack of concentration. It's people who think of themselves before anyone else, who frankly aren't very nice.

"He has this almost idealistic way at looking at the game," Shepherd says. "It's basically how could anyone not have the sole idea of doing whatever is necessary to give his team the best shot to be successful? He can't fathom the idea that someone else might not think that way. He doesn't comprehend selfish."

Every year, Kruger puts in a call to see if Self can play in his annual golf tournament.

The Kansas coach took over for Kruger at Illinois in 2000 -- he even looked at Kruger's old house, though he didn't buy it -- and the two remain friendly.

For a variety of reasons, mostly due to scheduling conflicts, Self always has to decline the invite.

"Instead of saying, 'One of these damned years you're going to do this damned thing,' he just says, 'That's OK, Bill. We'll get you another time,'" Self says. "He's just too darned nice. No one -- I mean no one -- is going to say anything bad about him. He won't [get a] negative recruit. He won't do anything but do his job and go about promoting his program. He's really good, and really good for our sport."

The really good part, that's what people sometimes don't understand. Kruger's name will not be the first -- or probably the 15th -- when people are asked to name the best and most successful coaches in the game today. Yet he's a savant -- Glass remembers NBA scouts jotting down his inbounds plays at Florida -- and a masterful rebuilder. Texas-Pan American, Kansas State, Illinois, Florida and UNLV were a combined 78-99 in the year before he arrived at the respective campuses. They were 117-72 by his second year in charge.

The shift at Oklahoma is equally impressive. The Sooners were 27-36 in the two years before he arrived, and living with the stain of an NCAA investigation. Now Oklahoma is making its second consecutive Sweet 16 and spent three weeks as the No. 1 team in the nation, the program's first time atop the rankings since 1990.

But ask Kruger to talk about any of that and he waves it off, somehow twisting any question about himself into an answer about his team.

He might be a stud at any sport he tries, but he's a flat-out dud when it comes to self-promotion.

Kruger has simple goals. You won't find self-help sayings or mottos wallpapered around the locker room. "Our goal is to get better every day," Henson says. "People want to hear more than that and some people make it glitzier, but really that's what everyone is trying to do."

And he has simple pleasures. This, after all, is a man who spent seven years in Las Vegas and loved nothing better than hitting the Sin City Red Robin for postgame dinner.

Oklahoma has afforded him the space to own a speck of land. His wife, Barbara, has horses, and he has a tractor, a slightly larger version of the toy he used to mow his little patch of land in built-up Gainesville years ago. When his players come over for team functions, Kruger even lets them ride the horses.

"It's like a little pony party," sophomore Khadeem Lattin says.

Usually after he hosts the players for dinner, Kruger will break out a vat of ice cream for dessert. Sometimes he'll get a little crazy, maybe mix up a little malt if they want to spice it up.

He usually prefers his ice cream straight.

Vanilla, just like the man himself.