To mark the return of heavyweight boxing to Washington, Mayor Marion Barry has proclaimed today "Riddick Bowe Day." With its dawning, the public bantering between Bowe and ex-champion Pinklon Thomas has ended, to be replaced by what all involved hope will be a slugfest.

The six-bout card tonight at the 3,500-seat UDC Physical Activities Center signifies another step in the return of the District as a site for prominent fights. Said D.C. Boxing and Wrestling Commission Chairman Jeffrey Gildenhorn: "This city has a lot of talent, the facilities and great fans. We're going to continue going after boxing because boxing is good for our city."

Much of the attention has been focused on Bowe (18-0), now a resident of D.C., who captured the silver medal in the 1988 Summer Games in Seoul in the super heavyweight class.

But Thomas (30-4-2), who held the World Boxing Council belt for two years, cannot be overlooked. He has lost to several journeymen during an arduous comeback -- the latest defeat at the hands of unranked Mike "The Bounty" Hunter -- but swears he's ready for the best Bowe has to offer.

A Bowe victory likely would mean a berth on the undercard of the Oct. 25 Buster Douglas-Evander Holyfield heavyweight title fight, with a potential title bout for himself soon after. A Thomas victory could mean a date for himself with former champion George Foreman in the fall.

Promoter Rock Newman said yesterday that more than 1,900 tickets already have been sold for tonight's card. Gildenhorn, in remarks two weeks ago when he was sworn in to his position, said the UDC arena will be one of the primary sites for big-time boxing in the future, along with the D.C. Armory, the Washington Convention Center and Coolidge High School.

Included on the undercard: Two Washington junior lightweights, one hoping to ascend into the top 10 ranks, the other a veteran looking to recharge his professional career.

Eugene "Sonny" Speed and Kenny Baysmore are two cogs in the vibrant D.C. boxing scene and will lead the undercard with their 10-round bout. Speed, 27, has fought 10 years at various local sites (including four bouts at Coolidge) and will battle to remain undefeated.

"A win should put me in the top 10 and in place for a title shot," said Speed (18-0). "Kenny's experienced, but he's had his chance."

Baysmore, 29, has a 24-3-2 professional record. The Washington native began his amateur career in 1976 and has boxed professionally for 10 years.

D.C. lightweight Sharmba Mitchell returns for the first time since a fifth-round TKO of Freddy Sevilla July 20.

Trainer Adrian Davis has had Mitchell on a vigorous schedule, with bouts about once a month, accounting for his quick rise into the upper echelons of the lightweight rankings.

On the latest World Boxing Council list, Mitchell is 22nd. He is ranked 12th by the North American Boxing Federation and 10th by the World Boxing Organization.