At 6:15 a.m. today, minutes after dawn, Mike Tyson walked out of prison with controversial promoter Don King and co-managers and longtime friends Rory Holloway and John Horne. Tyson got into the back seat of a waiting black limousine where he was greeted by the new woman in his life, Monica Turner, a third-year medical student at Georgetown University.

Tyson largely was shielded from view as he emerged from the one-story red brick reception area of the Indiana Youth Center by a tall man who spread his full-length black coat. Some photographers and cameramen, from a world-wide media assemblage of hundreds, shouted while struggling for an unobstructed view after having waited for hours in the cold and dark.

The former heavyweight champion, 28, who has said he became a Muslim during the three years he served for raping a beauty contestant in an Indianapolis hotel room in 1991, wore a white prayer cap, indicating his intention to attend an Islamic service before being flown by private jet from the nearby Indianapolis airport to his mansion in rural Southington, Ohio, between Cleveland and Youngstown.

Tyson, with media in pursuit in cars, was taken swiftly about two miles down narrow country roads to a large red brick mosque at the Islamic Society of North America, where a special prayer service of thanksgiving was offered by Tyson's new spiritual adviser, Muhammad Siddeeq. Another former heavyweight champion, Muhammad Ali, greeted Tyson in the mosque and joined in the prayers, which lasted about a half hour.

Tyson -- who could produce a $25 million fight even against a tuneup opponent perhaps as early as summer and an unprecedented $120 million blockbuster against 46-year-old George Foreman, Riddick Bowe or unretired Evander Holyfield -- looked somewhat drawn and tired. The 5-foot-10 fighter appeared to weigh a bit less than his best boxing weight of 218 pounds, sharply reduced from the 275 pounds he weighed when he entered prison. He wore a dark suit coat without a collar, dark trousers and a white shirt without a tie, and has grown a light beard.

"I am very happy to be out and on my way home," Tyson said in a statement that was handed out. "I will see you all soon." He thanked people for their support, which included numerous pieces of mail. A sign reading "May Allah Bless Mike Tyson" was hung in the mosque. King knelt directly behind Tyson amid some 200 Muslim worshipers and took part in the service.

Turner, 28, who reportedly has visited Tyson regularly during the last three years, waited out of view during the prayer service.

"She has been there for him," said Rev. Charles Williams, a Baptist minister and president of the Indiana Black Expo who invited Tyson to the ill-fated festivities four years ago. Williams, who also visited the boxer frequently in prison, promised a "new" Tyson while acknowledging today that part of the changed man appeared to be his religion.

Tyson emerged from the prison to twin walls of media and satellite dishes that lined both sides of the prison road. Four television news helicopters hovered. Fans and the curious lined the two-lane road beyond the prison property, but could not get a glimpse of Tyson inside the limousine as it turned at the front entrance.

An outdoor area across the road from the prison had been cordoned off as a possible prayer site, but Tyson opted to go to the mosque. Siddeeq thanked King, Holloway and Horne for "allowing" Tyson to attend. Then Ali, wearing a blue suit, met privately with Tyson and others for several minutes before Tyson's limo departed at 7:30.

Tyson now must serve four years probation, undergo psychoanalysis and perform 100 hours of community service a year as part of his punishment in the rape of then-18-year-old Desiree Washington. His six-year sentence was cut in half for good behavior.

The rape came after years of tumult in Tyson's life in and out of the ring. The youngest heavyweight champion in history at age 20, Tyson faltered badly after beating Spinks. He fired his manager, Bill Cayton, and trainer Kevin Rooney, and let himself get out of shape, losing the undisputed heavyweight title in February 1990 on a knockout by 42-1 underdog Buster Douglas.

Tyson's personal life also crumbled. He broke his hand in a Harlem street fight with boxer Mitch Green in August 1988, had a brief and stormy marriage with Robin Givens, drove his mother-in-law's BMW into a tree claiming he was trying to kill himself and broke a TV cameraman's lens in anger. In October 1990 he was found guilty of battery for fondling a woman, but only had to pay a $100 fine.

"He's 100 percent different," said Siddeeq. "He's on a different path. He's not reached an angelic state. He does not levitate. But he's still a wonderful person.

"I know he wants to breathe some of the good fresh air out here. The temptations will be there. He'll fail like all of us. The difference is his conscience. He's striving to be upright. He has a sensitivity toward being a good person. Here was a man who let the words fly. Now he says, Damn,' and he'll say, Excuse me.' "

Tyson had been baptized in a Baptist church in Cleveland in a four-hour ceremony attended by King on Nov. 27, 1988. Rev. Jesse Jackson prayed over Tyson on that occasion.

What changes have occurred to Tyson the boxer after a four-year layoff also are a matter of huge interest. He last won a lackluster decision from Razor Ruddock on June 28, 1991, running his record to 41-1. "It's going to take a while to chip off that rust," trainer Angelo Dundee, who works in Foreman's corner, said recently.

Tyson has been away from boxing even longer than Ali, who missed 3 1/2 years (March 1967 to October 1970) when he was barred from the sport for refusing induction into the military. As great as Ali was afterward, his former trainer, Dundee said, "We lost the best years of Ali." The time off hurt Ali's speed and reflexes in particular.

Turner and the few others in the Tyson group made the short flight to Ohio and the 14-room mansion Tyson moved to in 1989 after becoming familiar with the area from visits to King, who has a home close by. When he arrived in Southington today, Tyson was greeted with yellow ribbons and banners on the wrought-iron security gates leading to his 60-acre estate. CAPTION: After serving 3 years for rape, Mike Tyson (white cap), with promoter Don King behind him, and entourage, leave the Indiana Youth Center in Plainfield.