NBA Power Rankings: Rockets slide to No. 4 after Harden's injury

With Stephen Curry back with a bang for the Golden State Warriors and James Harden going down with a hamstring injury for the Houston Rockets, the divide between the defending champs and the rest of the NBA is starting to grow as the calendar flips to 2018.

Every week throughout the regular season, our panel (ESPN's Kevin Arnovitz, Amin Elhassan and Ramona Shelburne, The Undefeated's Marc J. Spears and FiveThirtyEight's Chris Herring) will rank the league's 30 teams from top to bottom, with research notes on each team provided by ESPN Stats & Information.

Previous rankings: Week 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1

1. Golden State Warriors
2017-18 record: 29-8

There were absolutely no signs of rust in Curry's return after he missed 11 games with a sprained right ankle: 38 points on 17 shots and 10 made 3-pointers in a win against the Grizzlies. One of the greatest shooters of all time had his most efficient night: an effective field goal percentage of 105.9, which takes into account the added value of a 3. Curry has 556 career games with at least 10 shot attempts; this was his highest effective field goal percentage in any of them. -- Vincent Johnson

2. Boston Celtics
2017-18 record: 30-10

The top team in the Eastern Conference has the easiest schedule in January, according to ESPN's Basketball Power Index, but Boston will face a tough test in its first game of the month, a rematch of the season opener against the Cavaliers. Boston is 4-2 against the league's top six teams, tied with the Thunder for the best in the NBA. -- Vincent Johnson

3. Cleveland Cavaliers
2017-18 record: 24-12

The Cavaliers have lost four straight road games, tied for their longest streak since LeBron James returned to Cleveland. There's no better time for the long-awaited Cavs debut of Isaiah Thomas, who is set to take the court Tuesday against Portland. Cleveland then faces a five-game road trip with the first stop coming against Thomas' former team, the Celtics, a game he'll sit out. Thomas averaged 28.9 points per game last season in Boston, the second-most in a season in Celtics history. -- Vincent Johnson

4. Houston Rockets
2017-18 record: 26-9

The Rockets have lost five of their past six games, and now James Harden is out at least two weeks with a strained hamstring, but Chris Paul has proven more than capable of running the offense without Harden. This season with Harden off the court, Paul has a player efficiency rating of 37.1 (18.2 with Harden on the court) and has scored or assisted on 64 percent of the Rockets' points. Houston has outscored opponents by 89 points in 196 minutes with Paul on and Harden off. -- Vincent Johnson

5. San Antonio Spurs
2017-18 record: 25-12

The Spurs have eight double-digit losses this season, their most entering January in the past 20 seasons. That also matches their total from all of the previous season. But they're still the Spurs, currently sitting third in the Western Conference as they continue to ease Kawhi Leonard back into his superstar form. -- Vincent Johnson

6. Toronto Raptors
2017-18 record: 25-10

While you were watching the College Football Playoff on Monday, DeMar DeRozan became the first player in NBA history to score 50 points on New Year's Day, according to the Elias Sports Bureau. He set a franchise record with 52 points and the most-improved part of his game shined through: his passing. DeRozan dished out eight assists to bring his points scored and assisted total to 71 points, more than half the Raptors' total points (131) in the overtime win. -- Vincent Johnson

7. Minnesota Timberwolves
2017-18 record: 24-14

Jimmy Butler is back to playing at an All-NBA level. He averaged 26.5 points per game in December despite struggling from the outside. Butler shot 57 percent on 2s and a scorching 93 percent from the free throw line. According to Second Spectrum, Butler was the most effective player in the NBA while driving to the rim, as he averaged 1.21 points per chance, best among the 60 players with at least 100 drives. -- Micah Adams

8. Oklahoma City Thunder
2017-18 record: 20-17

The Thunder finished December with the third-best record in the NBA at 12-5. In that time, Russell Westbrook found himself in a familiar position, first in the league in usage rate (37.8), coinciding with a decrease in the same category for Carmelo Anthony and Paul George from the first two months of the season. The biggest difference for Westbrook: His 3-point attempts per game are down (5.6 to 4.3) and drives per game are up (17.0 to 21.5). -- Vincent Johnson

9. Washington Wizards
2017-18 record: 21-16

Now's a good time for the Wizards to make a push as they have the NBA's third-easiest schedule in January, according to ESPN BPI. The Wizards have won six of their last seven home games and enter a stretch in which six of their next seven games are at home, with the lone exception being a trip to Memphis. -- Micah Adams

10. Milwaukee Bucks
2017-18 record: 19-16

Yes, he stepped out of bounds. But the Greek Freak's game-winning dunk over Westbrook was still an impressive display of athleticism and aggression with the game on the line. It was the NBA's third game-winning dunk in the final five seconds of a game this season after there were none in all of 2016-17. It was also the 52nd contested dunk for Giannis Antetokounmpo, most in the NBA according to Second Spectrum. -- Vincent Johnson

11. Detroit Pistons
2017-18 record: 20-15

With no obvious go-to scoring threat, the Pistons have become one of the NBA's best at manufacturing points. Take for instance their movement on offense. According to Second Spectrum, Detroit utilizes over 107 off-ball screens per game, nearly 10 more than the second-ranked Warriors. The fulcrum for all of that action? Tobias Harris and Andre Drummond, who rank first and second in total screens set. Per Second Spectrum, Harris has set over 100 more off-ball screens than any other player in the NBA. -- Micah Adams

12. Denver Nuggets
2017-18 record: 19-17

Three teams have had the same player start at point guard in every game this season: Westbrook with the Thunder, Kyle Lowry with the Raptors and Jamal Murray with the Nuggets. The next step for Murray is to become more of a playmaker at the position. He's averaging 2.7 assists per game, the fewest among all point guards to make at least 10 starts this season. -- Vincent Johnson

13. Portland Trail Blazers
2017-18 record: 19-17

Damian Lillard has missed Portland's last five games with a strained hamstring, but the Blazers have gotten huge shots from unexpected places in his absence. They're 3-2, with each of their wins decided by one or two possessions. In the final five minutes with the score within five points, Al-Farouq Aminu, Maurice Harkless and Evan Turner are a combined 5-for-5 from deep. -- Vincent Johnson

14. Indiana Pacers
2017-18 record: 19-18

Could a lingering injury impact Victor Oladipo's chances at snagging an All-Star spot? The first voting update is due Thursday, so we'll soon find out where Oladipo stands among the fans. ESPN's Real Plus-Minus views Oladipo as an All-Star as he ranks 10th in the NBA -- fifth in the East -- in RPM. -- Micah Adams

15. Miami Heat
2017-18 record: 19-17

The Heat rank 27th in the NBA in points in the paint (40.4) and free throw attempts (18.9) per game despite ranking third in the league in drives (50.3) per game. For a Miami team that's top-10 in the league in making 3s -- something that hasn't happened since 2012-13 -- being able to complete plays in the paint will give this offense some more diversity. -- Vincent Johnson

16. New Orleans Pelicans
2017-18 record: 18-18

The Pelicans are perfectly average: 18-18 on the season, 9-9 at home, 9-9 on the road, 4,002 points scored and 4,004 points allowed. In games that are decided in the final five minutes with the score within five, they're 11-11. Making this team's performance much more head-scratching is that with All-Stars DeMarcus Cousins and Anthony Davis, a duo the league has no answer for, the Pelicans are still so exceptionally ordinary. -- Vincent Johnson

17. LA Clippers
2017-18 record: 16-19

Lou Williams averaged 28 points per game last week to help the Clippers to a 3-0 mark. Williams is having a career year, averaging more than 21 points despite coming off the bench in all but seven games. He has been a stabilizing force for a team that has used a league-high 16 starting lineups as it continues to shuffle key pieces. -- Micah Adams

18. Philadelphia 76ers
2017-18 record: 17-19

Starting with the Christmas Day win over the Knicks, the 76ers reeled off three wins in four games last week, a nice recovery from a stretch in which they lost nine of 10. They host the Spurs on Wednesday to begin what promises to be a difficult four-game homestand that includes games against the Pistons, Celtics and Raptors. January is a big month for Philly, as it has the NBA's third-hardest schedule this month behind only the Clippers and Warriors. -- Micah Adams

19. New York Knicks
2017-18 record: 18-18

There's no denying that Kristaps Porzingis can do lots of things on the hardwood and that he has all the makings of a perennial All-Star. And yet if you had some bones to pick, you'd probably start with rebounding and playmaking. Among the 30 players with the most starts at power forward this season, Porzingis ranks just 21st in rebound percentage and 23rd in assist percentage. All this despite standing 7-foot-3 and handling the ball as an undisputed No. 1 option. -- Micah Adams

20. Utah Jazz
2017-18 record: 16-21

The Jazz have been abysmal on the road this season. Not only are they 3-15, tied for the worst away mark in the NBA, but they've lost each of their last four by an average of nearly 25 points per game. Even worse, they play eight of their 13 January games on the road. -- Vincent Johnson

21. Chicago Bulls
2017-18 record: 13-24

Despite struggling in Monday's overtime loss to Portland, in which he had four assists and eight turnovers, Kris Dunn has shown serious promise during the Bulls' surge from the cellar. Since the 3-20 start and entering Monday's game, Dunn was averaging 8.1 assists and 1.9 steals per game, numbers matched over that 13-game stretch by only reigning MVP Russell Westbrook, four-time MVP LeBron James and MVP favorite James Harden. -- Micah Adams

22. Charlotte Hornets
2017-18 record: 13-23

Charlotte's lone win last week is also the best one it will likely have all season, winning at Oracle Arena despite entering just 2-12 on the road and as a double-digit underdog. Most of the credit goes to Dwight Howard, who looked like a totally different player with his playmaking and shotmaking. Howard had seven assists and five in the fourth quarter, which set a career high for assists in any quarter. He also managed to knock down three midrange jumpers to also tie a career high. -- Micah Adams

23. Dallas Mavericks
2017-18 record: 13-25

Don't look now, but the Mavericks are owners of the NBA's longest active win streak, with all four wins coming against teams currently .500 or better. They've done it with a balanced effort as four different players -- J.J. Barea, Dirk Nowitzki, Dennis Smith Jr. and Harrison Barnes -- have led them in scoring. That streak will be put to the test Wednesday as they host the Warriors, who could potentially get caught looking ahead to their showdown at Houston on Thursday. -- Micah Adams

24. Phoenix Suns
2017-18 record: 14-24

Unfortunately for the Suns, Josh Jackson hasn't been one of the standouts in what's proving to be one of the strongest drafts in years. Jackson currently ranks 455th out of 457 players in Real Plus-Minus, struggling particularly on the offensive end where he's posting a true shooting percentage of 44 percent and an assist rate of just under 8 percent. Among players to take at least 250 shots, only Lonzo Ball has posted a lower TS percentage. -- Micah Adams

25. Brooklyn Nets
2017-18 record: 14-23

The absence of D'Angelo Russell has paved the way for Spencer Dinwiddie, who is averaging twice as many assists and field goal attempts than he did last season. Did you know that Dinwiddie has the most 30-foot 3s this season? He has more than Stephen Curry, James Harden, Devin Booker, Klay Thompson and Eric Gordon combined. Dinwiddie has shot 50 percent from 30-plus this season; those five stars have combined to shoot 20 percent. -- Vincent Johnson

26. Sacramento Kings
2017-18 record: 12-24

Can the 40-year-old Vince Carter get some more minutes? When he plays 16 minutes or more, the Kings are 4-3 this season. When he plays fewer than that, they're 4-11 and when he doesn't play at all, they're 4-10. -- Vincent Johnson

27. Los Angeles Lakers
2017-18 record: 11-25

The Lakers have dropped seven straight, including five without Lonzo Ball, who has not played since Dec. 23. Luke Walton has praised Ball's ability to push the pace and it's one area in which his absence has been felt. Entering Christmas, the Lakers ranked first in the NBA in pace. In the five games since without Ball, they've played about four possessions per 48 minutes slower at a pace that's ranked eighth. -- Micah Adams

28. Atlanta Hawks
2017-18 record: 10-26

Which player leads all rookies in Player Efficiency Rating? Is it Ben Simmons, the leading candidate for Rookie of Year? Nope. Is it Jayson Tatum, who leads the NBA in 3-point percentage? Try again. The answer is John Collins, who has a 21.2 PER this season. If only some wins could come with all that efficiency. -- Vincent Johnson

29. Memphis Grizzlies
2017-18 record: 12-25

The Grizzlies, who once held their hat on defense, rank 28th in the NBA in defensive efficiency since the start of December. In that span, they've struggled against good competition. They're 1-11 against teams .500 or better and 4-1 against all other teams. -- Vincent Johnson

30. Orlando Magic
2017-18 record: 12-26

That 8-4 start feels like an eternity ago. Since then the Magic are an NBA-worst 4-22, ranking 30th in offensive efficiency and 29th in defensive efficiency. Orlando is only making it harder on itself, as evidenced by Elfrid Payton getting blocked by his own hair on Monday. -- Micah Adams