With only six days left in the regular season, three of the eventual 12 NBA playoff teams know the positions they will occupy in postseason action next week.

The NBA's curious playoff system (clubs complete almost five months to eliminate only 10 of 22 league teams) is designed to create this kind of uncertainly down the stretch.

It's worked out that way this season, much to take league office's delight, because Denver, Phoenix, Washington and Portland have faded near the end of the schedule while Milwaukee, Seattle, Los Angeles and Cleveland became hot.

Golden State in the Western Conference and New Orleans in the Eastern have outside chances of squeezing in, but their hopes are slimmer than Georges Gervin's waist.

Portland, Philadelphia and San Antonio are the only clubs who know today what they will be doing next Tuesday and Wednesday.

Those three division champions will be sittion out the first round. Denver, which played Buffalo last night trying to wrap up at least a tie for the Midwest title, should grab the fourth bye from the fast-closing Blucks.

The mathematical possibilities of these final few days are endless. Here is a look at how each conference shape for the playoffs:

In the East, Washington (41-37) is climbing precariously to the No. 3 spot behind Philly and San Antonio.The Bullets have lost six of their last eight homes games and are as unpredictable as Bowie Kuhn's next baseball decision.

Their last four games - home against Los Angeles tomorrow, on the road against Boston in Providence on Thursday and Philadelphia on Saturday before ending in Capital centre Sunday against the 76ers - are against teams that always have given them matchup problems. If they lost all four, they could wind up as low as sixth, although that win its last four, which is unlikely.

But the Bullets could fall as far as fifth, and lose the home court advantage in the first round, unless they win at least one game. If they end in a tie with Cleveland for the fourth and fifth spots, they'd move to fourth because they have a better record against conference teams.

NEW YORK (40-38) is a game behind the Bullets and one ahead of Cleveland (39-39). If New York can get by Atlanta (38-40) tonight in Madison Square Garden, the Knicks could finish strongly, because their remaining games are against Detroit, Kansas City and Buffalo.

Clevland, playing more consistently, has a tough home test against Milwaukee on Thursday followed by a game at Atlanta on Friday. The Cavaliers also play Buffalo and Kansas City.

If the Bullets finish third, they would meet Atlanta in the first round. If they finish fourth or fifth, it would be either New York of Cleveland.

In the west, Seattle's amazing ability to win on the road, coupled with L.A.'s inability to win must games, has kept things extremely tight.

Because division champs automatically draw first-round byes. Phoenix will occupy the No. 3 spot in conference playoffs although the Suns will finish with a better record rhan Denver.

The Phoenix opponent in the first round is the question. Milwaukee is No. 6, but the Bucks are only two games behind No. 4 Seattle and one behind No. 5 Los Angeles.

The Lakers have the tougherst remaining schedule, with road games at Milwaukee and Washington, a Forum meeting with the Nets and a season-finale at Portland.

Seattle plays three of its last four at home: Houston, Phoenix and Golden State, Its last road contest is against the Warriors.

Milwaukee would prefer that its playoff position isn't determined by its final game. That happens to be in Boston on Saturday - John Havlicek's birthday. The Bucks also have to contend with L.A. and San Antonio at home and Cleveland on the road.

In the battle for the best record in the NBA, Philadelphia has an outside shot at overcoming Portland. If the Trail Blazers win two of their last three at home they wrap it up, and that shouldn't be hard, espcially if Bill Walton plays