The easiest team to underestimate in college basketball is Kansas State. The immediate instinct is to laugh, for its uniforms are the sort of two-tone purple nobody beyond a beer league would dare ware in public. And the center, Ed Nealy, might not be able to jump 10 inches if you dangled the Hope Diamond over his head. The coach is a conservative grump who says of his offense: "We're not averse to running. We scored 70 points once this year."

Lots of teams take a quick look at those Wildcat duds and the fatty center inside one of them, notice that the only players on the team taller than 6-foot-7 hardly ever escape the bench and assume victory before the opening tip. Oh, bye, thy name is Kansas State. They usually leave the gym losers, mumbling to themselves, as Illinois did after the NCAA West region semifinal: "We just didn't execute well."

Next to losing to the Wildcats, the worst thing imaginable, it seems, is admitting they just might be superior. Few teams do. This leads to the undestandable paranoia evident at a press conference today, 24 hours before the Wildcats meet North Carolina for the region title, when Rolando Blackman was asked if the team considered itself the NCAA's Cinderella team this season.

"No," he said. "because that suggests that we don't belong in the tournament. I think we do belong. No, I don't go along with that at all."

No one who has seen them beat San Francisco, Oregon State and Illinois disagrees with Blackman, the thoughtful Olympian more comfortable now in Manhattan, Kan., than his native Manhattan, N.Y. Few also would disagree that 27-7 Carolina has more better players than 24-8 State, or that State will offer one fine challenge when the teams meet Saturday at 1:15 p.m. (WRC-TV-4).

The player with all the virtues that make State special is not necessarily Blackman. He is unselfish, disciplined, poised and fiercely competitive in the critical moments of a game. But he is obviously talented, a man clearly capable of routine brillance on any team in America. The player who makes us wonder at the unusual breed of Wildcat each game is Nealy.

He is 6-7 and 235 pounds, give or take a ton, something in the order of a white Wes Unseld, cerebral and silent, seemingly nailed to the floor and yet somehow always in possession of more rebounds than his taller and more mobile opponent.

"With some players," said Carolina Coach Dean Smith, " a rebound hits thier hand and bounces off. Nealy catches it. He has hands like Bobby Jones and Adrian Dantley. He is going to be a great pro some day. I truly mean that."

The Smith pregame syrup has some substance. Nealy's best performances nearly alsways come in postseason games, against such as Oregon State's Steve Johnson.

Last season, Nealy scored 56 points hitting 22 of 37 shots, and grabbed 37 rebounds in State's League and NCAA playoff games against Nebraska, Kansas, Arkansas and the eventual national champion, Louisville. He more than held his own against Oregon State's Johnson last week and mustered 12 points, 14 rebounds and three steals against taller Illinois Thursday.

He has a nice touch from the outside, which will be useful against Carolina's Sam Perkins. Like Unseld, he passes quite well and occupies so much space a rebound often has nowhere else to fall but into his hands. Only State and Yale considered him a prospect worth more than casual attention after his senior season in Bonner Springs, Kan.

Yale was vastly apealing, he discovered on a recruiting trip, but too far away and less basketball-minded than State. A junior, he is one of seven KSU players with a cumulative average of at least a B and one of three on the Big Eight all-academic team.

The Wildcats and their underated coach, Jack Hartman, are going to have to be their brainiest Saturday, because the Tar Heels are bigger and more mobile inside. Carolina embarrassed one of the best frontcourts in the country during a five-point victory over Utah Thursday.

Hartman is one of the few coaches bright enough to find a way to keep the ball from Carolina's Perkins and James Worthy inside. If not America's zonemaster, he has enough ways to make Carolina do what it least prefers: bomb from the outside. Carolina might have to use the 6-9 Worthy to contain the 6-5 Blackman, a highschool center at ease anywhere on the court.

Still, Hartman admits: "I would give anythig to have three or four days to prepare for Carolina, for all the different looks on offense and defense. They really load you up preparing for them in a day. What you have to do is play your game and hope it's adequate."

Hartman's team runs better than he would like opponents and casual fans to realize, scoring at least 70 points in half its regular-season games. But the Heels will be the ones most anxious for a track meet ysaturday, the ones likely to press and trap on defense and shoot earlier on offense.

Almost immediately after his team beat Illinois, Hartman was snappish. He seemed to take offense at a relatively tame question about how he thought his team would fare against Carolina, saying: "We know they're an outstanding team. We read about 'em often enough, see 'em on television all the time." The State paranoia was public again.

Today, Hartman was as outgoing as he ever gets. Once or twice, he even smiled. Which meant he was pleasantly evasive instead of sourly so. He is a disciple of Henry Iba, for whom he played in the late '40s, and a boyhood hereo of Kansas Smith.

"During the season," he said and Blackman and Nealy nodded nearby, "I am very serious, not that easy to please. I have great respect for the game, great respect for the profession."

Two of the best minds in basketball will be going at one another Saturday, Smith with the better players. They were coy about everything except for the general notion that whoever controlled the pace of the game probably would win.

"We've done well at tempo this season," Blackman said, "and they've done well. Now it's a matter of who can get it done first."