James "Buster" Douglas, the 70-1 shot who in February startled the civilized world by laying five consecutive wallops against the head of Mike Tyson and leaving him ring-dead in Round 10, is now waging the second most important bout of his life. It is being fought in a New York federal court, where the new heavyweight champion and promoter Don King are having the law on each other. The stakes are very high.

Douglas wants out of his contract with King, who is flourishing a document that he says spells out that Douglas is indentured to him for the next two years. Douglas's motives in this matter are twofold. One is fiscal. He is determined that King's sticky fingers shall have no part of the $60 million Douglas has been offered for his next two fights.

Douglas's other motive is highly personal. He has a fiery hate for King, and understandably so. He views King, his promoter, as no less than the in-house scoundrel who, on the very night Douglas accomplished the boxing upset of the ages, tried mightily to job him out of his title on behalf of Tyson, whom King also promotes.

Thereby King breached his contract, Douglas and his attorneys contend, saying he did so with egregious acts of treachery and bad faith, "as the architect of a deliberate scheme to overturn the result in favor of Tyson."

It was, indeed, obvious that King was not trying to protect the interests of Douglas that night in Tokyo, or even remain neutral. The Douglas people were speaking of King's actions at ringside when he almost went apoplectic after Douglas survived an eighth-round knockdown, screaming, "Long count! Stop the fight!"

After King saw his man, Tyson, counted out, he was in a new rage and resorted to a try at regaining from outside the ring the title that Tyson lost inside it. There is testimony that he persuaded Jose Sulaiman, his longtime chum who bosses the WBC, to "suspend" the award of the title to Douglas, which he promptly did until overwhelmed by the reaction of public opinion a day later.

King's influence with boxing bodies that are sometimes paid as much as $150,000 for "sanctioning" King's fights has never been much of a secret. According to one witness, he lashed out at Sulaiman during the fight with "Look at what you've done. What kind of referee did you bring me from Mexico? You're going to get my man beat." After the fight the intimidated referee actually tried to confess that he had given Douglas extra time, though a review of the tapes tells of no long count.

In that New York courtroom the stakes are high, because in the big fights King sometimes appropriates huge amounts unto Don King enterprises. By detaching himself from King, Douglas could keep more of the big loot that he has been offered for his next two defenses and free himself from King's machinations.

The world of boxing always has been known to be a curious one. It is an industry in which yesterday's hates are transformed into today's love matches, with untroubled ease. Testifying for King is his rival promoter Bob Arum, who at one time yielded to no man in his despise of Don King as a truly loathesome creature.

It is remembered that only a few weeks ago, Arum was on Douglas's side, agreeing to promote his next fight for $2 million in full knowledge he was violating the contract King held on Douglas. As boxing figures often do, Arum had an easy explanation. "I threw caution to the wind," he said.

Arum, who later fell out with the Douglas group, was full of quips the other day in the courtroom. Arum, on King's ringside screaming that Tyson won the fight: "A protest is a correct procedure. You yell your head off, otherwise nobody pays any attention." Also, "In the heat of combat, we all say crazy things we are not accountable for."

It was years ago that Don King gave the term "promoter" a new dimension. Unlike Tex Rickard, Mike Jacobs, Jim Norris and other promoters of legend who were content to stage fights and not invade the manager's domain, King invented a new tactic. When he couldn't wean a fighter away from his installed manager, as in the case of Bill Cayton and Tyson, he simply superimposed himself on the manager's property, calling himself "the promoter," and did business with Tyson.

King belongs near the top if not at the top of all of boxing's fascinating characters. As a promoter, he not only manages to take a cut from the purse; nobody fights anybody in King's stable unless he signs King on as his promoter. When Joe Frazier, who fought for King, lost his title to George Foreman, King turned up as Foreman's promoter. King later boasted, "I came with a champion and left with a champion." He calls this type of thing, this methodology, "trickeration."

And for blitheness of spirit, none matches King. He knows no embarrassment. Twenty-four hours after screaming "Long count!" in Tokyo and demanding that Tyson be awarded the fight, King told the New York Times it was never his intention to have Douglas's victory overturned. Now there's a man you can believe.