Like King Lear raging at nature, Marvin Hagler lopes across the sand dunes hurling invective to the skies near his training camp at Provincetown, 120 miles from here at the tip of Cape Cod.

As the June sunrise breaks over the Atlantic, Hagler conjures up images of demons and devils as he jabs at the air with his fists and shrieks with unrestrained fury.

The current demon for Hagler, the World Boxing Council and World Boxing Association middleweight champion, is Vito Antuofermo, whom he will fight Saturday at Boston Garden.

"Every fighter has his own way of psyching himself up for a fight and this is how Marvin does it," said Goody Petronelli, who, with his brother, Pat, has orchestrated Hagler's boxing career since the day he walked in off the street to Petronelli's Brockton gym 13 years ago and he wanted to become a fighter.

Saturday's bout will be the second between the two. They first met in Las Vegas in November 1979, when Antuofermo held the middleweight title, and the judges ruled that one a draw, permitting the Italy-born Antuofermo to retain his crown.

"We won that fight," said Petronelli. "I want my title back," said Antuofermo, who lost his championship to Englishman Alan Minter. Minter yielded the title to Hagler in London last September in a fight tainted with ugly racial overtones.

"I am not letting any black man take the title from me," Minter was quoted as saying, and, after Hagler knocked him out in the third round, the London crowd pelted Hagler and his entourage with bottles and debris.

With a professional record of 51-2-2 and 42 knockouts, Hagler's ascent to the title has been gradual, unlike the meteoric rise of Sugar Ray Leonard, to cite one example. At 29, Hagler is known to be bitter that the fat purses won by fighters he considered inferiors have eluded him for so long, and now that he has the title he has vowed never to lose it.

Patient and methodical, with an assortment of punches, he is also capable of pouncing on and making short work of a weakening opponent.

Characteristically, he has refused to participate in the traditional prefight hype for the Antuofermo showdown, remaining in seclusion in Provincetown and observing a schedule that he has described as similar to that in jail.

It is also characteristic of Hagler that, while he refused to interrupt his training schedule for the media, he did agree to return two weeks ago to Brockton, where he is the most popular local hero since the late heavyweight champion, Rocky Marciano, to lead the town's centennial celebration parade.

Frank Stoddard, a reporter for the Brockton Enterprise who has covered Hagler's career since its beginning, says that while outside the ring Hagler is warm and soft-spoken and enjoys appearing for civic and charitable causes, when it comes to a fight "he works himself up into a frenzy of hate.

"He won't even shake hands with someone he might have to fight someday," says Stoddard. "But after a fight he'll shake hands and go to their parties."

Says Ida Lang, Hagler's mother who moved her family to Brockton from Newark shortly after the 1967 riots: "He's two different people.In the ring, he's mean and tough. Outside, he like to be with his wife and family and he loves kids."

As a child, Hagler had always wanted to be a fighter and kept a poster of Floyd Patterson in his room, his mother said.

With a shaved head as his trademark, Hagler has defended his title only once before, easily defeating Venezuela-born-Fulgencio Obelmejias on a technical knockout in the eighth round last January in Boston.

Joe McLaughlin, a friend and neighbor of Hagler's, said, "I'm 55 years old and I've been following boxing since I was a kid. Marvin's a throwback to the old-time fighters. He loves to train for a fight and he loves to fight. He's not like some of these younger kids who get everything all at once."

For Antuofermo, 28, Saturday's fight represents what most boxing experts feel is his last chance.A notoriously easy fighter to cut, he was badly beaten by Minter in an attempt to regain his title, emerging from that match "a bloody pulp" by his own camp's description.

Antuofermo came to the United States as a teen-ager and settled in Brooklyn. Arrested in a street fight, he was given the choice of reform school or participating in a New York Police Athletic League boxing program and chose the latter, thus beginning his career.

He turned pro in 1971 as a walk-on, replacing a fighter who did not show up for a four-round bout, and earned $100. But in recent years, he has been chronically troubled by bleeding over the eyes and, after the last bout with Minter, considered retiring. Instead, last November he underwent an operation in which the bones under his eyebrows were filed down in an effort to correct the problem.

In April, Antuofermo won a decision from Mauricio Aldana in Chicago although he went down twice in the first round.In Boston this week, he has been highly visible, unlike Hagler, even staging a sparring exhibition Wednesday in front of city hall to promote Saturday's bout.

He says his bleeding problem is improved and, "I'm ready for the bell to ring."