The National Basketball Association is back in prime time, with two crowd-pleasing teams to showcase to the nation.

This will be the second time in three seasons the Philadelphia 76ers, as Eastern Conference champion, and the Los Angeles Lakers, as the best of the Western, have met for the NBA title. The series should be a classic confrontation between two finesse teams that enjoy entertaining almost as much as they like winning.

The Lakers, who won the 1980 championship in six games, begin their best-of-seven championship series rematch with the 76ers Thursday at the Spectrum in Philadelphia (WDVM-TV-9 at 9 p.m.).

It should be a fast-breaking, wide-open, run-and-gun full-court affair, matching the two teams with the most individual talent in the league. And, for the first time in three years, CBS will televise all weekday games of the series in prime time, 9 p.m. EDT.

The last playoff game to be televised nationally in prime time by a network was the fifth game of the Washington Bullets-Seattle SuperSonics series, June 1, 1979. Game 2 of this series will be played in Philadelphia Sunday at 1 p.m. and Games 3 and 4 in the Inglewood, Calif., Forum Tuesday June 1 and Thursday June 3.

While the 76ers were having two physical series with Milwaukee and Boston, beating the Bucks in six games and the Celtics in seven, the Lakers beat Phoenix and San Antonio in four straight. Los Angeles is the first team in NBA history to sweep two consecutive best-of-seven series. The Lakers also set a league record with six straight playoff road victories.

The Lakers will have had a record 11 days off before starting this series. Coach Pat Riley said the layoff "shouldn't bother us; we've had them before," but added that he preferred to start the series tonight.

The NBA purposely started the season a month later than in the past and set the playoff schedule so the final could be shown live during the week and avoid the May ratings sweeps, which end Wednesday.

Riley gave the Lakers two days off after the San Antonio series and gave them last weekend off. He practiced them hard yesterday and said they would work out at home today and Wednesday before going to Philadelphia Wednesday afternoon.

The 1980 series is best remembered for the sixth game, at the Spectrum, when Kareem Abdul-Jabbar was left in Los Angeles with a sprained ankle. Magic Johnson moved to center, scored 42 points, had 15 rebounds and seven assists, and the Lakers won, 123-107, to take the title.

Johnson is doing it all again for the Lakers in these playoffs, averaging 18.3 points, 11.6 rebounds and 10.3 assists. "I'll let Kareem pull his own weight this time, though," he said. "I ain't bailing him out no more. We feel like we can't lose, because we haven't in so long, but if we do, we just do. It won't kill us. We'll just go out there and try to win the next game."

The Lakers haven't lost since April 13. They won their last three regular-season games and all eight playoff games. Since March 24, they have won 23 of 27.

They also have stepped up the pace in the playoffs. During the regular season they averaged 114.6 points a game and yielded 109. In the playoffs, they are scoring at a 117.8 rate and giving up only 107.

The teams split their two regular-season games and the Lakers didn't do much better containing Andrew Toney than the Celtics did. Toney, who scored 39 points in an earlier playoff victory over Boston and 34 in the seventh game, scored 46 against the Lakers on March 7, making 21 of 29 shots in a 119-113 Philadelphia victory at the Spectrum.

Johnson is expected to start out guarding Toney, with Michael Cooper relieving him.

"It should be a great series," Riley said. "I'm really looking forward to it. I think we match up better with Philadelphia than we do with Boston, and since we both want to get into a running game it should be a fun series to watch and a fun one to play. But we're out to win."