Don King matches Mike Weaver and Michael Dokes for the WBA title, possibly the penultimate step toward unification of the world heavyweight championship. Elsewhere, the last one and only, Muhammad Ali, vows to cut all ties to boxing.

King said in New York he has Weaver signed to fight No. 1 contender Dokes in September and if Weaver wins, he can have a rematch with WBC champion Larry Holmes.

No such promise yet to Dokes, managed by promoter King's son Carl. Nothing like having two heavyweight champs in the stable for awhile.

Ali, in Tulsa to help start a nightclub boxing series, said, "No way I've come here to box . . . No one told me I was expected to get inside a boxing ring. I just don't jump into a ring with anybody. I'm 40. I'm finished. I'm in no shape to box . . . Last time I'll be involved . . . I just don't want to hang around boxing rings and gymnasiums."

The Weaver-Tex Cobb cancellation brings another development, Thomas Hearns filling in on CBS this Sunday. Jeff McCracken (19-0) will give Hearns (34-1) his third test as a middleweight. What about Hearns eventually trying Sugar Ray Leonard again for the unified 147-pound title? "Not as a welterweight. I'm not going back to welterweight anymore" . . .

Rare accident at world fencing tournament in Rome: Vladimir Smirnov, Soviets' Olympic 1980 and world 1981 foil champion, dueling Matthias Behr of West Germany when Behr's weapon pierced Smirnov's mask, left eye and brain; hemorrhage, coma resulted. Condition serious--as U.S.S.R. four-man foil team won gold medal anyway . . . In northeast Ohio, John Seece, 25, declares end of auto racing career; debris flying from his wrecked stocker Sunday at Cloverleaf Speedway killed Dianna Petersen, 8 (a twin).

Tour de France: Pascal Simon of France won 126.7-mile, Alpine 15th stage, in 6:34:41. Bernard Hinault extended overall tour lead to 3 minutes plus . . . Italians, fresh from cheering Azzurri World Cup soccer champs, now have Azzurra: 12-meter yacht launched at Pesaro to campaign for '83 America's Cup . . .

No. 7 (Joe T) returns to Channel 7 (see TV Column, Style), and when Ara Parseghian joins Brent Musburger this fall as in-studio analyst on NCAA football, it will be Northwestern's last winning coach with NU student newspaper reporter of that Ara, er, era . . . Steelers' quadruple Super Bowl TE Randy Grossman retires at 29, a Pittsburgh restaurateur . . . Not voluntarily retiring: ex-Oiler Kenny Stabler, "open for offers." Reckons, says lawyer Henry Pitts, he can help somebody in NFL on short notice; might like USFL life in Birmingham.

Capital Hilton gets into the new D.C. swing, ballroom boxing, Friday 8 p.m. Sports Encounters presents 6-6, 227-pound Dave Johnson (fought Greg Page, Renaldo Snipes) in feature against Ed Smith . . . In Atlanta, 7-1, 235-pound Tree Rollins, threatening for months to sue M.L. Carr, has done it: Hawk center demands $4 million damages, accusing Boston Celtic guard of "verbally and physically" abusing him during 40 NBA games--worst, in Boston Jan. 13, when Carr allegedly "overtly threatened" him during play and afterward "brandished what appeared to be a razor or knife in a threatening manner." Celtics' boss Red Auerbach on the suit: "One of the most ludicrous things in the history of sports."