1. Atlanta Hawks (Record: 33-8; last week's rank: 2): The Hawks leapfrogged the Warriors to take over the No. 1 spot thanks to their 12-game winning streak and victories in 26 of their past 28 games.
2. Golden State Warriors (Record: 32-6; last week's rank: 1): The Warriors are still winning at an elite level, but Atlanta made the margin of error so slim that one loss last week dropped Golden State.
3. Memphis Grizzlies (Record: 29-11; last week's rank: 7): The Grizzlies will celebrate MLK Day by honoring ex-NBA players Earl Monroe, Chauncey Billups and Jason Collins.
4. Portland Trail Blazers (Record: 30-11; last week's rank: 3): The Clippers, Memphis and San Antonio gave Portland a three-game losing streak. Is that reason not to believe in the Blazers as a legit power?
5. Houston Rockets (Record: 28-13; last week's rank: 5): Terrence Jones is expected to return soon after being out since Nov. 3 with a leg injury. How will that affect Josh Smith and Donatas Montiejunas?
6. Dallas Mavericks (Record: 28-13; last week's rank: 6): The Mavericks are 10-1 when Chandler Parsons scores more than 20 points.
7. Los Angeles Clippers (Record: 27-14; last week's rank: 9): When Clippers coach Doc Rivers faces his old Celtics squad on Monday, there will be no player left from the 2008 championship team he coached. Rajon Rondo was the last before being traded.
8. San Antonio Spurs (Record: 26-16; last week's rank: 10): The Spurs added a versatile scoring forward in D-League Austin’s JaMychal Green, who was getting interest from other teams.
9. Washington Wizards (Record: 28-13; last week's rank: 11): Veteran forward Paul Pierce has quietly been a strong mentor for his young teammates, most notably John Wall.
10. Chicago Bulls (Record: 27-15; last week's rank: 4): Perhaps the most interesting game on MLK Day is Derrick Rose and the Bulls going to Cleveland to face LeBron James.
11. Phoenix Suns (Record: 24-18; last week's rank: 12): Phoenix has won 12 of its past 16 games, averaging 111.4 points during that span. The Suns also are in the midst of an eight-game home stand.
12. Toronto Raptors (Record: 26-14; last week's rank: 8): January has not been kind to the Raptors, who are 2-6 this month. They suffered back-to-back home losses recently for first time this season.
13. Oklahoma City Thunder (Record: 20-20; last week's rank: 14): Guard Dion Waiters is settling in as a dependable bench scorer, averaging 16.8 points the past five games.
14. Detroit Pistons (Record: 16-25; last week's rank: 19): Thanks to their surge after waiving Josh Smith, Detroit is now one game behind Brooklyn for the East’s eighth and final playoff spot.
15. New Orleans Pelicans (Record: 20-20; last week's rank: 13): Anthony Davis could return from his foot injury Monday at New York. His next visit to New York will be as an All-Star.
16. Milwaukee Bucks (Record: 21-19; last week's rank: 16): The Bucks are not in a hurry to replace guard Kendall Marshall, who suffered a season-ending knee injury, a source told Yahoo.
17. Denver Nuggets (Record: 18-22; last week's rank: 15): The Nuggets are mailing out media kits promoting Ty Lawson for the All-Star Game with a T-shirt, hat and mug stating, “I LOVE TY.”
18. Cleveland Cavaliers (Record: 21-20; last week's rank: 18): Knowing they are a Kyrie Irving injury from more trouble, the Cavs are working to acquire a veteran point guard.
19. Miami Heat (Record: 18-22; last week's rank: 20): Dwyane Wade has missed the past two games with a hamstring injury, but is questionable for Tuesday’s game against the Thunder.
20. Sacramento Kings (Record: 16-24; last week's rank: 17): Twenty-two-year-old forward Quincy Miller, who signed a 10-day contract on Saturday, could be a steal for the Kings.
21. Brooklyn Nets (Record: 17-24; last week's rank: 22) One NBA executive found it comical the Thunder tried to acquire Brook Lopez, who has had a series of foot problems, years after failing center Tyson Chandler’s physical because of a foot injury.
22. Charlotte Hornets (Record: 16-25; last week's rank: 21): Former Bobcat Tyrus Thomas is averaging 14.5 points for D-League Iowa.
23. Utah Jazz (Record: 14-27; last week's rank: 23): Rudy Gobert is averaging an NBA-best 4.4 blocks. Ex-Jazz center Mark Eaton holds the NBA record with 5.5 per game during the 1984-85 season.
24. Indiana Pacers (Record: 15-27; last week's rank: 24): Indiana has had a winning record at home for 25 straight years (the NBA’s longest active streak), but are 8-11 this season.
25. Los Angeles Lakers (Record: 12-29; last week's rank: 25): Kobe Bryant, 38, recently told The Los Angeles Times that retiring has crossed his mind.
26. Boston Celtics (Record: 13-25; last week's rank: 26): The Celtics opened a roster spot by cutting guard Chris Douglas-Roberts. They could fill it with a 10-day contract signing.
27. Philadelphia 76ers (Record: 8-32; last week's rank: 27) Anadolu Efes Istanbul forward Dario Saric, drafted by the Sixers in 2014, has averaged 9.4 points and 6.0 rebounds through 13 games.
28. Orlando Magic (Record: 15-29; last week's rank: 28): Rookie Aaron Gordon is returning from foot surgery just in time to make a late push to get selected for the Rising Stars Challenge.
29. Minnesota Timberwolves (Record: 7-32; last week's rank: 29) Free agent Jeff Adrien, recently cut by Minnesota, is hoping to return to the NBA later this season after playing for China Guangdong.
30. New York Knicks (Record: 5-36; last week's rank: 30): The Knicks have lost a franchise-worst 16 straight games and 26 of their past 27. There is no reason for optimism.
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