Power Rankings: Three-way race for top spot By Marc Stein | ESPN.com

Monday, Jan. 2

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The Dallas Mavericks' courtesy hold on the top spot in ESPN.com's weekly NBA Power Rankings didn't make it to halftime of their first game.

The Miami Heat rolled up a 35-point lead on their old friends from Dallas before the fourth quarter on Christmas Day, then used that rout to fuel the first 5-0 start in franchise history, quickly sending LeBron, D-Wade & Co. to the rankings summit.

Perhaps we're showing too much of the respect we always grant to the reigning champs, given how old and slow and out of shape no less of an authority than Dirk Nowitzki says they look, but the Mavs have clung to their spot in the top half of the rankings despite a humbling 1-4 start. Only the fact that three of the Mavs' four losses came to teams in the top four has kept them from falling below No. 15. For now.

Denver (No. 9 to No. 4), Orlando (No. 12 to No. 5), Portland (No. 14 to No. 6) and Philadelphia (No. 16 to No. 9) are the big climbers since the preseason rankings of Dec. 23. Taking a double-digit tumble, along with the Mavs, are Memphis (No. 8 to No. 19) and New Jersey (No. 19 to 29).

Check back every Monday during the regular season for a fresh and fully nonautomated pulse take of the league's 30 teams, which is compiled with Steve Nash-esque dishing from ESPN Stats & Information and the Elias Sports Bureau. Click here to comment on these rankings.