The ASAP Treatment Center here is the National Basketball Association's version of the Betty Ford Center, an exclusive "rehab and detox" facility for players who want to kick a habit - and practice their slams at the same time.

"We're the only drug treatment center in the country with NBA-approved breakaway backboards," says Dr. David Lewis, ASAP founder and director.Since Lewis signed a contract with the NBA four years ago, 14 former and current players have checked into the private facility. Average stay: 45 to 48 days. Cost: $450 to $500 a day, most of it covered by the player's medical insurance.

Former patients still in the NBA are Orlando Woolridge, Quintin Dailey, Walter Davis of Denver, William Bedford of Detroit, John Lucas of Seattle, Roy Tarpley of Dallas and Chris Washburn of Atlanta.

Utah's John Drew, Houston's Lewis Lloyd and Mitchell Wiggins, and New Jersey's Micheal Ray Richardson, who are no longer in the league, went through the program. Houston's Dirk Minniefield is currently a patient, as are former players Duane Washington of New Jersey and David Thompson of Denver.

"It was a tough adjustment for the first couple of weeks, but when you get used to the regimen, the place is a home away from home," said Woolridge, who stayed at the facility for 51 days early in 1988.

Like other celebrity-studded treatment facilities, ASAP tries to camouflage its institutional aspects and create a laid-back, friendly environment. Plenty of plants. Soothing murals. Therapists in blue jeans. Family visits. Open, friendly dialogue with the staff. Everything geared to ease a patient's predicament and keep him from wanting to run back to the real world.

"You get bored from time to time," said Woolridge, who played ball with Bedford during his stay. "There's other things you want to be doing and can't - like shopping. But it's not like you can just leave."

Indeed, quitting the program would result in suspension without pay by the NBA.

ASAP is at Van Nuys Community Hospital, occupying the east wing as well as six bungalows on the grounds. Players stay in the east wing for the first 25 to 30 days of treatment, sleeping in hospital-like rooms without TV or telephone, and then move to the homier bungalows, which have kitchens and living rooms. Food is standard hospital fare.

The white stucco bungalows, with their orange tile roofs and pool in the courtyard, would appear to make up an ordinary, middle-income apartment complex were it not for an occasional Mercedes in the garage and the expensive talent on the undersized basketball court. Lewis, a self-described "exercise nut," prescribes a daily dose of basketball as part of every player's treatment.

"Physical exercise is helpful in recovery," Lewis said. "It is a perfectly good addiction."

Players go through detoxification without such drugs as Valium or methadone, Lewis said, and receive "12-step therapy," the procedure established by Alcoholics Anonymous in which the addict must first admit he's powerless over the drug. Among the other steps are a "spiritual awakening" and helping others get off drugs.

Daily sessions with counselors, all of them recovering addicts, are designed to resolve the "root conflict," such as low self-esteem, that led to the player's addiction, Lewis said.

Said Quintin Dailey: "I learned why I went to drugs and how to deal with life, and I found out a lot about myself. It's OK to be Quintin. I don't have to be the basketball player all the time."

A typical NBA player at the facility awakens at 6:30 a.m., earlier than other patients, to start a rigorous workout that includes lap swimming, playing volleyball, riding stationary bikes, working at weight machines and, of course, playing basketball. Players get about 90 minutes of court time a day, often drafting other patients for games of H-O-R-S-E. If more than one player is there, they play one-on-one.

"I was probably in the best condition of my life when I came out," said Dailey, who was a patient twice for a total of 75 days about three years ago.

The players' extensive workouts - they can be as long as three hours a day - are the only difference between their rehabilitation program and those of the other patients, who don't exercise nearly as long.

All patients are put on a rigid schedule, which includes several hours of counseling and group therapy and nightly AA or Cocaine Anonymous meetings. The facility has a patient-staff ratio of 2-to-1 and can accommodate as many as 30 adults.

Surrounding players with other addicts is a key part of therapy; it gives them a sense of fellowship, Lewis said, "so they don't feel they're out there all by themselves. There is something very powerful about a fellowship of people who have had the same problems and can go to that fellowship for strength and support."

In the AA tradition, an addict is never considered cured. After-care is continuous and lifelong, with players required to attend AA-type meetings in their hometowns and to see local counselors recommended by ASAP.

"We think our anti-drug program is working," said Gary Bettman, NBA vice president and general counsel.

And it's working, Bettman said, thanks to Lewis and the league's tough drug policy. If NBA security forces catch a player using cocaine, as Wiggins was caught, or if a player is arrested for cocaine possession, as Washington was, he is banned from the league for at least two years.

The NBA, though, needs more than just suspicion to test a player for drugs. The league has to gather enough evidence to convince the players' union that there is reasonable cause for a urinalysis. If the union agrees, the evidence is then presented to an arbiter, usually a retired judge, who makes the final decision on whether to test a player.

Players who voluntarily turn themselves in for treatment are given what Lewis calls "three strikes and you're out." The first time a player goes in for treatment, he gets his NBA salary while he is under Lewis' care. The second time, he isn't paid. If a player goes in a third time, he is banned for at least two years.

"It's a pretty strong deterrent," Woolridge said.

When a player goes to his coach or general manager for help, he is considered in a crisis situation, and strict procedures are followed. The team is instructed to call Lewis, who then sends one of his staff members to get the player and accompany him to the center.

"Once they get to us, they're addicted," Lewis said.