The advance notices on tonight's Potomac Valley AAU Boxing Championships at the Washington Coliseum tag 20-year-old Don Steiman as a "blond bombshell from Arlington" who will be taking on Aaron Caldwell in the 139-pound open division final.

"I've never heard that one before," said a laughing Steinman, who lives with his parents in Silver Spring. "That's funny, because I actually have short, black, curly hair."

Bombshell or not, Steinman's attitude is likely to be a bit grimmer when he takes on Caldwell, a Cardozo High graduate who made quick work of two preliminary opponents.

Caldwell, who has knocked out 14 of 16 challengers in the first round in just six months of amateur boxing, eliminated Wallore Dewes 16 seconds into their quarterfinal bout two weeks ago. Last Saturday he eliminated favored Jeff Passero within 40 seconds in the semifinals.

"He's a knockout artist, no question," said Pepe Correa, of Caldwell, one of 36 fighters of mixed ethnic backgrounds he handles at the Latin Connection, a club Correa runs in the basement of the Calvert United Methodist Church at 14th Street and Columbia Road NW.

"No one can match him pound for pound. I can't even work him with the junior welterwrights - his punch is too hard," Correa said. "We work him with the heavy middleweights, but I don't want to put him in the open welterweight class until he can carry 147 pounds.

"He's achieved in six months what takes most fighters two or three years to do."

At 6-foot-1, Caldwell, 20, will have a nine-inch height advantage over Steinman to go with his weighty right hand. But Steinman, known as "Little Rocky" at Finley's Athletic Club where he works out, knows what a hard blow really feels like.

The night before he was to register for the District Golden Gloves Tournament in February, Steinman totaled his Chevy Malibu in a 3 a.m. accident.

In addition to cuts, bruises and a slight concussion, the former Kennedy High football player splintered a tooth and was on soft foods for almost a week.

"I'm really lucky to be alive," said Steinman, who was 2-3 in novice competition before the accident. "The next day I went to see the car and I almost got sick. There was blood everywhere."

Steinman never made it to the Golden Gloves tourney where Caldwell captured the 139-pound novice title.

Tonight's fight will be Steinman's first in open competition - his preliminary victories were both by forfeit.

The card, labeled one of the best in the history of the Potomac Valley AAU by one official, begins at 7 with five junior division nontitle bouts. A 147-pound "box-off" will follow between Darrelll Smith and Mike James, with the winner to meet Robert Sawyer in the open final later in the evening.

There are nine novice bouts and 10 open fights scheduled, including a 112-pound clash featuring 1978 national AAU champion Bish Cullins against Al Martino of the Ham Athletic Club. The Dunes Hotel. (WJLA-TV-7, WJZ-TV-13, 5 p.m.)

Leonard, from Palmer Park, Md., is fresh from a March 24 knockout of Argentina's Daniel Gonzales. Leonard stopped Gonzales at 2:03 of the first round, his quickest decision to date.

The left-handed Viruet, Ring's No. 7 junior welterwright. carries a 15-3 record, including five knockouts, into the fight, his first of the year. His last bout was Oct. 17 when he took a 10-round decision from Bruce Curry at New York's Madison Square Garden.

Viruet's only other fight in 1978 was a loss by decision to Roberto Duran in April. He shared the U.S. lightweight Golden Gloves title with his brother Edwin in 1968. He has never been knocked out.