On a day when Magic went poof, the University of Kentucky used an improvised stratagem and the precise free-throw shooting of Kyle Macy to beat Michigan State, 52-49, in the championship game of the NCAA Mideast Regional yesterday.

Macy, a sophomore guard, scored 14 of the last 22 points made by the nation's No. 1-ranked college basketball team. Of those, 10 came on free throws, including four in the final 39 seconds that twice gave Kentucky three-point leads over a State team that once led by seven points.

So Kentucky advances to the national semifinals, the final four next weekend in St. Louis, where it continues its quest for a fifth NCAA title by meeting the West Regional winner.

And Earvin (Magic) Johnson, Michigan State's ballhandling prodigy, will be watching it all on the tube. A breathtaking performer all season, Magic was little more than a medicine-show huckster this day. Only two-of-10 shooting, he committed six turnovers and later said, "My whole tournament was bad."

Unable to work efficiently against State's aggressive zone defense in the first half, Kentucky trailed, 27-22, at the Intermission. As the teams came back to warm up for the second half, Leonard Hamilton, Kentucky assistant coach, earned his pay for the season.

"We had to get Macy some shots some way," he said."So, I said, 'Let's set a pick for him out there.'"

Coach Joe B. Hall loved the idea. He called Macy and big man Rick Robey to the sideline and there, on a clipboard, drew up the plan. Robey would move out past the free throw line, setting screens there, and Macy would drive around him.

It worked perfectly. So perfectly, in fact, that Kentucky needed only two field goals the last 10 1/2 minutes. Macy draw fouls by going around Robey's screen and putting up 15-footers.

As much as the ploy may have been technically responsible for Kentucky's 28th victory in 30 games, it also created the first erosion in Michigan State's self-confidence. That may have been most important of all, for until then State's young team had played well.

"Their zone had been good," Hamilton said. "But when we set the screen for Macy, it just broke them down some. A guard couldn't get through and a forward would have to come up on Macy. It broke them down, and I did see them start to panio."

Panic set in on offense, too. State had built a 31-24 lead against Kentucky's man-to-man defense. But when Kentucky switched to a 1-3-1 zone two minutes into the second half, State chose to abandon the quick game that give it the lead.

State Coach Jud Heathcote ordered his Big Ten champions to pass the ball, hoping to lure two Kentucky defenders to the outside so that Magic Johnson could work inside.

Kentucky didn't bite. Though behind, Kentucky allowed State to kill time, "We just played a tight, smart zone and hoped that, sooner or later, they'd take a bad shot or make a turnover," Robey said. "And that's what happened."

It took eight minutes, but Kentucky finally caught Michigan State at 35-all when James Lee stole the ball out Johnson's hand and sped away for a slam-dunk that moved Kentucky crazies in the sellout crowd of 13,458 to an explosion of applause and cheers.

From there on, the game was Macy's.It was still tied, 41-all, when the 6-foot-3 guard made a 15-footer around a Robey screen. Fouled, Macy, a 90 percent shooter from the line, sank the free thdow for a 44-41 lead with six minutes to play.

The stretch drive was thrilling.But each time State scored from the field to move within a point, Kentucky came back with two free throws to attain the relative comfort of a three-point-lead.

It was 48-47, Kentucky, after Johnson passed to Greg Kelser for a dunk with 1:50 to play. Then Kentucky chose to take its time, killing the clock until Terry Donnelly fouled Macy with 39 seconds left.

As he always does, Macy first rubbed his hands on his socks, drying them. Then he bounced the ball three times, as he always does. From a deep crouch, he sighted across the top of the ball before finally shooting. In a gym alone once, he made 114 straight free throws.

"I didn't even think about the situation," he said, meaning he didn't consider the shots' importance. "I just go through my routine and shoot them."

At 39 seconds, he made them both. State came back with another field goal 16 seconds later to pull within a point, 50-49, and with eight seconds left Macy was fouled again.

Routinely, he made two more.

"We kept fouling the wrong guy," said Heathcote.