Darryl Gee, pride of the Columbia (Md.) Soccer Association and Oakland Mills High School, became a member of North America's premier soccer team at age 18 yesterday, the first U.S.-born black on the Cosmos.

Kikor Yepremian, the Giants Stadium-based club's general manager, might have exaggerated slightly in likening Gee's signing (one-year contract, salary undisclosed) to the Brooklyn Dodgers' bringing Jackie Robinson into organized baseball in 1946. But obviously the Cosmos are counting on Gee -- they gave up their top two 1981 draft choices to obtain rights to him from the Minnesota Kicks, who selected him as the No. 2 man in this year's NASL draft.

The Cosmos also dropped a forward and a midfielder yesterday, the better for Coach Hennes Weisweiler to tutor the prodigy, who will be free to pick up further experience with the U.S. youth team and the national team.

"This is what I want to do," said Gee, who began winning MVP laurels in the Columbia league at age 10. "I feel I can wait and learn on the bench for a year or two without any problem . . .I hope my signing will inspire more black Americans to take up soccer. I feel it is the sport of the '80s, more so than basketball or football" . . .

Red Auerbach's Boston Celtics, old and otherwise: Don Chaney hanging up a 12-year playing career to become assistant coach of the Detroit Pistons under Scotty Robertson . . . Cedric Maxwell, a free agent now, weighing what Auerback calls "an outstanding offer" to stay against bids from elsewhere in the NBA . . . Alternate center Rick Robey saying he expects to be traded as surplus now . . . And San Diego Clippers considering Bill Westphal, former Occidental College coach, for an assistant's post.Westphal's brother Paul (Sun turned Sonic) remarked that when he and Paul Silas were Celtic teammates, he told Silas, "You're going to be a coach someday. You're going to need a good assistant. I think my brother's the best guy for the job." Westphal says, "I guess he remembered . . . Silas has hired my brother Bill." Maybe . . .

Deaths: Bob Hoernschemeyer, 52, great halfback for Indiana U. and Detroit NFL; played on the last Lion championship teams, 1952-53; of cancer in Detroit . . . Erhardt Henry Heller, 70, in Kitchener, Ontario; a 15-year New York Ranger defenseman, he held the club record of 647 games played (1930s and '40s) until Harry Howell broke it . . .

But good news, John J. Gourley, the Touchdown Club past president, has rejoined the Lunch Bunch after recovering from major surgery . . .

Raymond Brown of St. Albans won the 800 meters in 1:50.32 in the TAC (used to be AAU) National Junior track and field championships in Knoxville, Tenn., Tuesday night; made the junior Pan American team, which will compete in Canada in August. So did Dwight Stephens of T.C. Williams High, by finishing second in the 5,000 in 14:14.88. Area athletes had some other high finishes, led by Cathy Rattray of Bethesda-Chevy Chase, victor in the women's 400-meter dash, in 53.66. U. of Virginia's Vince Draddy won the men's 1,500 in 3:50 flat . . .

Sylvester Fiers, a paraplegic, recently won three gold metals in the National Wheelchair Games championships in Champaign, Ill., setting records at 200, 400 and 800 meters; plus a bronze in the 100. And by now he ought to be in Arnhem, Holland, for the International Olympiad for the handicapped, also on the basketball team. He's 20 and a UDC student.