Abe Pollin, chairman of Capital Centre, is so enthusiastic about Sugar Ray Leonard's proposed comeback that he said yesterday Leonard could fight at the Centre rent free.

Pollin said he did not believe Leonard would get hurt and "it would be terrific if he fought here. This is his hometown and we'd love to have him."

But Pollin said, "Our problem is competing for fights against places like Atlantic City and Las Vegas, which use boxing attractions to lure people to gamble." FOOTBALL

Offensive tackle Marvin Powell, elected president of the NFL Players Association last week and a leader in the union's 1982 strike, has been placed on waivers by the New York Jets.

The Jets said they tried in vain to trade Powell. Coach Joe Walton, disturbed by an offensive line that was penetrated for a league-high 62 sacks last season, gave Powell the news.

"He said they wanted to go with younger guys," said Powell, a five-time all-pro after being the Jets' No. 1 draft choice in 1977; offensive lineman of the year 1982 in voting by the NFL coaches -- and the team's player representative . . .

When the Orlando Renegades made Iowa offensive tackle Mike Haight the No. 1 pick yesterday in the U.S. Football League draft for its first fall season, he hadn't heard that the Jets had cut Powell.

A week ago, Haight had been drafted by the Jets in the first round, the 22nd player picked in the NFL draft. Now he was No. 1 in the younger, struggling league. And, yes, he would think about playing in the USFL.

But if the Jets, as appears, are "making room for someone else," he said, "I hope it's me."

Tony Casillas, the Oklahoma nose tackle, was the No. 2 pick in each league -- by the Atlanta Falcons, now by the Arizona Outlaws. Casillas made it clear where his sentiments lay.

"Money's a big consideration," he said. "It doesn't make a difference what league . . . I'm looking for security."

The coachless, fieldless Baltimore Stars' picks included Navy's Napoleon McCallum, tabbed by the Los Angeles Raiders last week.

The USFL's fourth annual open draft, a separate entity from its territorial draft, was dramatically different from the NFL's. It was in a New York City hotel ballroom, all right, but no media hoopla.

Just one guy in a windbreaker who wandered in, sat down, picked up a free newspaper and read the classified ads . . .

Former University of Miami tight end Willie Smith said he was "going crazy" when he accused Hurricanes Coach Jimmy Johnson of telling NFL teams Smith had failed a school drug test.

Smith, drafted in the 10th round last week by the Cleveland Browns after expecting to go much higher, accused Johnson of getting back at him for opting to leave with a year of eligibility remaining. Now, he said, he has apologized to Johnson.

Smith showed positive in a routine test before last season. It was not cocaine, he said, and "It happened just that once." . . .

Wilbert Montgomery, the former Philadelphia Eagles star picked up by Detroit last year to fill in for injured Billy Sims at running back, only to reinjure his own knee after gaining just 251 yards, has retired from the Lions at 31 . . .

Joe Childress, 52, a star Auburn fullback (1953-55) who played and coached in the NFL and American Football League for 14 years, died in Kingwood, Tex., after a long illness. He was MVP in the 1954 and 1955 Gator Bowls.

The old Chicago Cardinals made Childress their top draft pick in the 1956 draft and he went on with the team to St. Louis, 1960-65. He led the Cardinals with 701 yards rushing in 1963. TENNIS

Boris Becker and his powerful serve routed Juan Aguilera, 6-2, 6-4, in the first round of the $615,000 Tournament of Champions on the clay at New York's West Side Tennis Club. Becker is seeded No. 2 behind Ivan Lendl, who was leading Francesco Cancellotti, 6-3, 2-2, when their night match was suspended overnight because of rain . . . . Martina Navratilova has been fined $1,000 by the Federal Aviation Administration for carrying a concealed gun and ammunition aboard an airplane, the FAA confirmed. The top player in women's tennis was caught with a .38-caliber Smith & Wesson, and ammunition, at the San Francisco airport March 2. "A mistake," she said at the time. HOCKEY

Former U.S. Olympic and New York Rangers coach Herb Brooks can become coach of the Winnipeg Jets if he wants, said John Ferguson, general manager of the NHL club. Brooks was in Manitoba for talks with Ferguson and Jets President Barry Shankarow. "I still have a couple of other people to interview, but the ball is in his Brooks' court," said Ferguson. AUTO RACING

Danny Ongais, practicing above 204 mph, escaped injury when his racer spun and smacked the first-turn wall at Indianapolis Motor Speedway. Ongais, 43, a veteran of nine Indianapolis 500-mile races, has had six crashes at the speedway, with this one the first since practice for the May 25 renewal began Saturday.

Later, Herm Johnson, 33, was not so lucky. Johnson, also running at 204-plus when his car's suspension evidently broke, hit the first-turn wall nearly head-on and landed in the hospital with severe open fractures of both feet and a broken back (no spinal cord damage).

Last year, Johnson crashed in practice: broken right arm, chest injuries.

Defending champion Danny Sullivan got his speed up to 211.764 mph, matching the best overall figure in 1986 practice, by Mario Andretti. COLLEGES

If a team in next year's NCAA basketball tournament has one player who tests positive for drugs, it may be kicked out of the competition, NCAA President Jack Davis said. "We think the institution and the team should bear some responsibility . . . "

Davis said this new wrinkle in the drug-testing program approved at January's NCAA convention, and applicable to any sport, was adopted by the NCAA Executive Committee this week . . .

The NCAA, abandoning a format that has decided its Division I baseball champion for 40 years, approved a Final Four tournament more conducive to television.

The current 40-team setup, in which eight teams advance to Omaha and play a double-elimination College World Series, will continue through 1987. The following year, the NCAA will invite 48 teams to the tournament with only four reaching the finals . . .

Linebacker Chuck Faucette and end Bruce Mesner on defense and tailback Alvin Blount on offense have been selected by their teammates to captain Maryland's 1986 football varsity.