When the 28th Atlantic Coast Conference tournament begins this morning at the Capital Centre there will be hoopla, controversy, big plays, bad plays clutch plays. There will be big spenders screaming their heads off. b

But there will be one thing missing. The thing that used to be the staple of the ACC tournament.

Pressure.

In the old days, before the NCAA postseason tournament expanded to 48 teams, this was the only way to get into the national championship. Now, Virginia, North Carolina and Wake Forest know they are in. Maryland and Clemson know they will be in with one victory.

Duke knows it has clinched at least an NIT bid. N.C. State knows one victory will probably put it in the NIT. Georgia Tech is just hopeless.

"It can't be the same as in the past, but that's good," North Carolina Coach Dean Smith said yesterday. "Now, the three best teams know they're in the NCAAs, so we're relaxed, just looking to play well. In the old days, all the pressure (the top seed) to prove that it's the best team. that's not fair. They've already proven it."

Yesterday, as five of the eight teams worked out at the Capital Centre -- Maryland stayed at Cole Field House and State and Tech chose not to practice -- there was a looseness in the air as the sound of bouncing basketballs echoed through the cold, empty arena.

Wednesday, is the day for everyone to dream. Today, at 11 a.m. when third-seeded Wake Forest and Clemson open the first-day, four-game marathon, reality will set in.

After the Deacons and Tigers play, Georgia Tech will attempt the impossible against Virginia at 1:30 p.m. N.C. State will play second-seeded North Carolina at 7 p.m. and Maryland will play Duke in the finale at 9:30 p.m.

The only news yesterday concerned injuries, Four North Carolina players -- James Worthy, Sam Perkins, Al Wood and Mike Pepper -- didn't practice on Tuesday. All practiced yesterday, including Worthy, who had his first workout since incurring a back injury a week ago.

The news was good for the Tar Heels but not for Duke. Coach Mike Krzyzewski said after practice tht 6-foot-8 center Mike Tissaw, who sprained an ankle in Duke's 66-65 overtime victory over North Carolina Saturday, is doubtful starter tonight.

He has not practiced since then, although he went through a couple of light drills yesterday. If Tissaw cannot start, Krzyzewski will either go with Chip Engellend in a three-guard line-up, or start 6-8 Allen Williams.

In either case, forward Kenny Denard will have to guard Terp center Buck Williams. Dennard shrugged off the significance of having to guard Williams.

"I've guarded him at times before and he hasn't done that much against me," he said. "Now you put that in the paper and that'll probably fire him up. But big deal. If he needs that to get him fired up now, something's wrong. I expect him to come out here like a wild man, anyway."

Williams probably will be wild. He learned yesterday that he placed sixth in the voting for the all-conference team, meaning he is on the second team for the second year in a row.

The Maryland center, who averaged 16.5 and and 11.6 rebounds a game, has said all season he would not be surprised if he were left off the all-conference team. Still, if Smith is correct, Williams will have a great tournament.

"Look back historically. The guy who finished sixth in the voting plays great in the tournament," the North Carolina coach said, "Wally Walker five years ago for Virginia; Gene Banks last year. In 1979 Dudley Bradley didn't even make second team and he has tournament MVP."

Most people expect this year's MVP to be Ralph Sampson, Virginia's 7-4 center who was voted player of the year. Sampson, like his teammates, was relaxed and dunk-happy during the Cavalier workout yesterday.

"We're taking it seriously," Sampson said when someone asked how Virginia regarded Georgia Tech, who was 0-14 in the conference. "This time of year, you have to take every game seriously."

Perhaps the most intriguing sight of the day was Virginia Coach Terry Holland, nattily attired in a black sweat suit, standing under one basket trading jokes with the same writers he wouldn't let talk to his players a year ago.

Second place had to go to Wake Coach Carl Tacy, who stood at center court, and in his normal monotone said, "This is the time of year when if you have any basket ball blood in you at all, it begins to boil."

Tacy didn't sound like his blood was boiling.