Years from now, it will be remembered as the night Charlie Thomas hung on the rim. It will be remembered as the night Dean Smith was saved by an official who decided the letter of the law was more important than the spirit of the law.

Because referee Hank Nichols, one of the more respected officials in basketball, called a technical foul on Wake Forest's Thomas for hanging on the rim even though Thomas did so to avoid injuring another player, North Carolina escaped the first round of the Atlantic Coast Conference tournament tonight with a 72-61 overtime victory over the Demon Deacons.

The Tar Heels (23-7) will play in the second semifinal here in The Omni Saturday against N.C. State (20-8), a 70-63 victor over Clemson. In the opener, Georgia Tech (22-7) will play Duke (22-6).

The top-seeded Yellow Jackets defeated Virginia, 55-48, today largely because the Cavaliers (15-15) failed to score for five straight minutes after cutting an 11-point lead to two with less than seven minutes to play. Duke routed Maryland, 86-73, to reach the semifinals.

But the game to remember was North Carolina-Wake Forest. With Delaney Rudd (24 points) doing his magician's act and Mark Cline scoring 16 points, the seventh-seeded Deacons (15-13) had the Tar Heels in trouble. Even though Kenny Smith scored 18 points, Warren Martin 16 and Joe Wolf 12, Wake Forest looked primed to pull an upset.

The Demon Deacons led, 47-39, with 7:35 to play after Rudd had buried an 18-footer. Moments earlier, the tension on the North Carolina bench had been apparent when Smith drew his first technical foul of the season, for screaming at Nichols about a foul called on center Brad Daugherty (14 points, 18 rebounds).

"Some of the calls inside, or the noncalls, were amazing," Smith said. "I was very disappointed. That's all I'm going to say. Next question."

The next question, the only real important question in this game, concerned the play involving Thomas, a 6-foot-7 freshman. The sequence began when Cline drove the right base line and was met by the 7-foot, 240-pound Martin, who was called for a block and fell underneath the basket.

Cline had already passed off to Thomas, who went up to dunk. Martin was still lying on the floor. Wolf later remembered yelling at Thomas, "Watch out."

"I hear Joe yell and I looked down and saw Warren," Thomas said. "I always thought the rule was that you can hang on the rim if you're doing it so you don't hurt somebody. I felt I had to do it. The ref (Nichols) told me I did the right thing but that he had to call it."

As soon as Thomas hung on the rim, Nichols signaled a technical foul. Kenny Smith made the technical to make it 47-44 with 6:05 left. And, instead of Wake getting the ball after Martin's foul, North Carolina got the ball. Wolf promptly hit a 10-footer to make it 47-46. Frazzled, the Demon Deacons turned the ball over, Smith making a steal for a layup that made it 48-47, North Carolina, with 5:30 left.

In 35 seconds, the Deacons had gone from a four-point lead with a chance to build it to six, to a one-point deficit.

Nichols said he had no choice. "We are trapped by the rule," he said. "The rule makes us call the foul. The only time a player may hang on the rim is if he is fouled while taking the shot. There is no rule allowance of possibility of personal injury for a player lying underneath. Whether it is right or wrong, I called it by the rule."

Fred Barakat, the ACC supervisor of officials, said there was no judgment to be made. "No way Hank should use judgment in that situation," he said. "It's a rule. The rule was violated. He had to make the call. Maybe the other 11 officials here wouldn't have applied the rule there. Maybe they all would have. I don't know."

"That obviously turned the game," Wake Forest Coach Carl Tacy said. "It broke our backs. He was trying to avoid an injury. What should he have done, come down on the player? Maybe that's what we'll have to teach in the future."

"If I were the official, I would have said it was all right," Wolf said. "It was the right thing to do."

Martin agreed. "Anyone who plays basketball would have done the same thing," he said. "Charlie made a good decision."

Remarkably, the Demon Deacons hung in. Thanks to the acrobatics of Rudd, they led, 53-52, with 1:21 to go after Rudd had gone through three Tar Heels for a spinning, circus layup. But Wolf followed a miss by Steve Hale (zero for nine in regulation) to make it 54-53 with 59 seconds left.

Rudd had a chance to put the Deacons ahead when he was fouled with 37 seconds to go, but made just one of two to tie it at 54. The Tar Heels held the ball until Hale missed from 15 feet with three seconds to go. Rudd rebounded and time ran out.

"I thought Delaney was fouled rebounding that shot," Tacy said. "But it takes a courageous official to make that call, and we didn't get it."

They also got almost nothing in overtime as North Carolina bolted to a six-point lead and never looked back. Once again, Smith and the Tar Heels had done their Houdini act.

Georgia Tech needed no such magic in the opening game of the tournament. The Yellow Jackets got 15 points, seven rebounds and six steals from Bruce Dalrymple and held off Virginia (which got 16 points from Jim Miller and 13 from Olden Polynice).

The Cavaliers shot six for 19 in the first half, shot 42 percent for the game, turned the ball over 22 times and still only trailed by 44-42 with 6:40 left. But with three chances to tie Virginia missed a bad shot (by Dan Merrifield), then turned the ball over twice.

Tech, given such gifts, took the victory and ran home happy even though it lost freshman Duane Ferrell, probably for the season, to a knee injury in the first half.

"Our defense won this game for us," Tech Coach Bobby Cremins said. Actually, Virginia's offense won it for the Yellow Jackets.

Besides Ferrell, most players injured in the day's action were in pretty good shape. Mark Alarie of Duke suffered a hip pointer and teammate Jay Bilas left the game with Maryland due to tendinitis in his knee, a recurring condition. Both are expected to play Saturday. Maryland's Jeff Adkins sprained his ankle, but, pending X-rays, is expected to be back for the NCAA tournament next week.