An important Thursday in the Association

Time's running out in this NBA regular season for many teams as battles continue over playoff spots and seedings. But the season can't end quickly enough for the San Antonio Spurs, whose lead in the Western Conference, once thought to be insurmountable, is diminishing by the day. San Antonio will try to slow its recent slide when it hosts the Boston Celtics on Thursday night on the front end of a national television doubleheader (8 pm Eastern, TNT).

After that the two teams chasing the Spurs in the West collide when the streaking Los Angeles Lakers host the Dallas Mavericks (10:30 Eastern, TNT).

First comes a Wednesday featuring several games involving playoff contenders. In what is likely a preview of an upcoming first-round Eastern Conference playoff series the Atlanta Hawks host the Orlando Magic (7 pm Eastern).

The Houston Rockets, who need to make up 2.5 games on eighth-seeded Memphis in these last couple of weeks, visit the Philadelphia 76ers, who are closing in on clinching a playoff spot in the East (7 Eastern).

In a battle between the six and seven seeds in the West the Portland Trail Blazers visit the New Orleans Hornets (8 Eastern).

And the Oklahoma City Thunder, closing in on clinching home-court advantage for its first-round series, visit the desperate Phoenix Suns (10 Eastern).

San Antonio had stayed exceptionally healthy all season, which helped them purr along with the best record in the league all season. And until just recently the Spurs looked like shoo-ins to own home-court advantage throughout the upcoming playoffs. But the injury bug has finally taken a bite out of the Spurs, and they're feeling the effects. Monday night San Antonio played not only without Tim Duncan, but also Manu Ginobili and Tony Parker, and lost at home to Portland 100-92. So San Antonio has lost four games in a row, and they're now just 3.5 games up on the Lakers, and 4.5 games ahead of Dallas, with eight games left to play.

The Spurs hope to have Ginobili and Parker back Thursday night, but Duncan is still out indefinitely.

Boston, meanwhile, lost at Indiana on Monday night 107-100. So the Celts are just 5-7 over their last 12 games. Boston is now tied with Miami for the two spot in the East, two games behind the top-seeded Chicago Bulls, with nine games to go on its schedule.

The Celtics won the first meeting with the Spurs this season back in January 105-103, shooting 61% from the floor on the night.

San Antonio is now getting +200 at oddsmaker.ag to win the NBA championship this season. The two-time defending champion Lakers, who have won 15 of their last 16 games, are the favorites on that board at even-money. Boston is now getting +150 to win it all, and Dallas is being offered at +800.