1. Oklahoma City Thunder (25-5; last week's ranking: 2): The Thunder earned the top spot and the NBA's best record with a statement win without Russell Westbrook against Houston. How long can Kevin Durant and the Thunder stay No. 1 with Westbrook expected to be sidelined through the All-Star break?
2. Miami Heat (23-7; last week's ranking: 5): Miami picked up a big win in Portland without LeBron James. James turns 29 on Monday when the Heat complete a four-game road trip at Denver.
3. Indiana Pacers (24-5; last week's ranking: 3): After losing two in a row, the Pacers responded with four straight wins. Indiana is beating opponents by an NBA-best average of 9.5 points per game.
4. Portland Trail Blazers (24-6; last week's ranking: 1): Injured rookie guard C.J. McCollum (foot) is expected to make his NBA debut shortly after New Year's Day, a source told Yahoo Sports.
5. San Antonio Spurs (24-7; last week's ranking: 4): The Spurs have a nice record, but are short on elite-level victories. San Antonio has lost to Oklahoma City and Houston (both twice) and Indiana, Portland and the Clippers.
6. Los Angeles Clippers (21-11; last week's ranking: 6): Blake Griffin entered this season a 61.1 percent career free-throw shooter, but has made 80.6 percent over his past eight games.
7. Houston Rockets (21-12; last week's ranking: 7): The Rockets have a good opportunity to get some rest with just two games before Howard plays his old Lakers team on Jan. 8 in Houston.
8. Golden State Warriors (19-13; last week's ranking: 10): The Warriors may have got their mojo back: They've won five straight games following a bad loss to San Antonio without their stars.
9. Phoenix Suns (18-11; last week's ranking: 8): Point guard Eric Bledsoe plays the Clippers on Monday in Los Angeles for the first time since they traded him during the offseason.
10. Dallas Mavericks (17-13; last week's ranking: 9): Dirk Nowitzki is averaging 22.9 points this month after averaging 20.4 in November. Monta Ellis is averaging 18.8 this month after averaging 21.4 in November.
11. Atlanta Hawks (17-14; last week's ranking: 12): Atlanta needs Elton Brand to step up. He is averaging five points and three rebounds in the past two games with injured center Al Horford out indefinitely.
12. Minnesota Timberwolves (15-15; last week's ranking: 13): Kevin Love has an NBA-best 27 double-doubles so far and is averaging 29.5 points and 13.9 rebounds in December.
13. Denver Nuggets (14-15; last week's ranking: 11): The up-and-down Nuggets are reeling, having dropped six straight games. Next up? Miami on Monday when James likely returns for the Heat.
14. New Orleans Pelicans (13-15; last week's ranking: 18): Swingman Tyreke Evans has picked up his game of late, averaging 20.2 points and 5.7 rebounds the past four games.
15. Memphis Grizzlies (13-16; last week's ranking: 19): The Grizzlies could be poised to climb: They've won three of their past four games and are hopeful center Marc Gasol can be back soon.
16. Los Angeles Lakers (13-18; last week's ranking: 15): Former Lakers assistant coach Brian Shaw faces the Lakers in L.A. for the first time as Denver's head coach on Sunday.
17. Charlotte Bobcats (14-17; last week's ranking: 16): Coach Steve Clifford challenged his players by saying they have "to get past the point where everybody is happy the Bobcats don't get beaten every night."
18. Detroit Pistons (14-18; last week's ranking: 17): Trouble in the Motor City? Keep an eye on the ongoing battle between forward Josh Smith, the Pistons' highest-paid player, and first-year head coach Maurice Cheeks.
19. Sacramento Kings (9-20; last week's ranking: 21): After coach Mike Malone called out his players publicly, the Kings beat Miami and nearly won at San Antonio.
20. Washington Wizards (13-14; last week's ranking: 14): While Washington has had injury woes, the team has the talent to be a winner with John Wall, Bradley Beal, Nene and Marcin Gortat.
21. Toronto Raptors (13-15; last week's ranking: 22): The Raptors are currently in first place in the weak Atlantic Division where every team has a losing record.
22. Boston Celtics (13-17; last week's ranking: 20): There was a lot of hype surrounding rookie forward Kelly Olynk entering the season. He's averaging just 6.4 points and 4.9 rebounds.
23. Chicago Bulls (11-17; last week's ranking: 23): Forward Luol Deng has missed four straight games with a sore left Achilles tendon and has said he is going to be cautious about his return.
24. Utah Jazz (9-24; last week's ranking: 26): Rookie point guard Trey Burke is quietly off to a respectable start, averaging 13.2 points, 5.1 assists and 3.2 rebounds.
25. Cleveland Cavaliers (10-20; last week's ranking: 24): The Cavaliers are in a forgettable stretch after losing five straight games and suspending center Andrew Bynum indefinitely.
26. Brooklyn Nets (10-20; last week's ranking: 25): After losing at Indiana on Saturday, the Nets continue their difficult three-game road trip at San Antonio and Oklahoma City.
27. Orlando Magic (10-20; last week's ranking: 28): The Magic won two straight games for just the third time this season with a victory against Atlanta on Sunday. The Warriors are up next.
28. New York Knicks (9-21; last week's ranking: 27): Knicks owner James Dolan told his players there won't be any trades. That, according to a league source, means only that the Knicks don't have any deals imminent.
29. Philadelphia 76ers (9-21, last week's ranking: 29): Michael Carter-Williams entered Sunday averaging 18.1 points. He was the only rookie averaging more than 14 points as of Sunday.
30. Milwaukee Bucks (6-21; last week's ranking: 30): The Bucks are the NBA's only team with fewer than eight victories. They have dropped three straight games and have a three-game road trip up next.