As we enter the fourth week of the 2021-22 NBA season, teams are beginning to approach the 10-game checkpoint.

While sample sizes are still relatively small, there is still plenty to take away from the trends that have been put on display thus far. Which hot starts are sustainable? Which teams will figure it out after sputtering out of the gate?

A good way to answer these questions is to identify each team's X-Factor, which our staff has done in this week's power rankings. As always, these rankings reflect what we've seen through three weeks of action and aren't a projection of where teams can land as the season progresses.

That said, let's get into the week that was…

The undefeated and the winless

Undefeated:  76ers (4-0), Cavaliers (4-0), Clippers (4-0), Nets (3-0), Suns (3-0),Warriors (3-0)

Winless:  Hornets (0-4), Rockets (0-4), Pelicans (0-3), Pistons (0-3), Timberwolves (0-3),

Biggest riser

Philadelphia 76ers:  14 → 5

Biggest faller

Los Angeles Lakers:  5 → 12

Weekly scoring leader

DeMar DeRozan - 33.0 ppg on 61.4 percent shooting from the field, 66.7 percent from beyond the arc and 86.2 percent from the free-throw line through three games.

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NBA Power Rankings 2021

1. Miami Heat

• Previous rank: 3
• Overall W-L: 7-2
• Last week: 2-1
• Upcoming:  at Nuggets, at Lakers, at Clippers, at Jazz

X-Factor: Tyler Herro’s Sixth Man of the Year campaign

Herro is off to a blazing start this season, averaging 21.3 points per game while shooting 47.4 percent from the field and 42.6 percent from 3. His scoring average is the highest of any player in the league coming off of the bench, and he’s also Miami’s second-leading scorer, providing a necessary punch on offence. If the Heat are going to reach their championship aspirations, they’ll need Herro to continue to produce at this level.

– Kyle Irving

ONE PLAY: The Heat are taking the form of a Kyle Lowry team

2. Utah Jazz

• Previous rank: 2
• Overall W-L: 7-3
• Last week: 2-2
• Upcoming: vs. Hawks, vs. Pacers, vs. Heat

X-Factor: Donovan Mitchell’s fourth-quarter scoring

After a slow-ish start to the season, Donovan Mitchell has picked things up on the offensive end for the Jazz, taking over down the stretch in wins over the Kings and Bucks. Last season, he was 11th in fourth-quarter scoring. While the Jazz’s team-first offence yields balanced results, they look their best when Mitchell is cooking late in games as the team’s best shot creator.

— Benyam Kidane

3. Golden State Warriors

• Previous rank: 4
• Overall W-L: 8-1
• Last week: 3-0
• Upcoming: vs. Hawks, vs. Timberwolves, vs. Bulls, at Hornets

X-Factor: Golden defence

Draymond Green is looking like the leading Defensive Player of the Year candidate. Andre Iguodala and Andrew Wiggins are flying around on the wings. Gary Payton II is pestering opposing guards off the bench. Stephen Curry is… turning into Dikembe Mutombo? Put it all together, and you’ve got the team with the best defensive rating in the NBA .

Oh, and the Warriors are doing this without Klay Thompson.

— Jordan Greer

MORE: How Wiggins is filling the void left by Thompson

4. Brooklyn Nets

• Previous rank: 6
• Overall W-L:  7-3
• Last week: 3-0
• Upcoming: at Bulls, at Magic, at Pelicans, at Thunder

X-Factor: James Harden returning to MVP form

No surprise here. For the Nets to compete with the best of the best without Kyrie Irving, they’re going to need Harden to find his groove again. Much has been made of his slow start this season, which could be a combination of him still working his way back from the hamstring injury he dealt with last season and some of the rule changes. A good sign for the Nets? Harden’s been better lately, posting a triple-double in Brooklyn’s win over Detroit, a 16-point, 11-assist double-double in its win over Atlanta and 28 points in its win over Toronto.

— Scott Rafferty

5. Philadelphia 76ers

• Previous rank:  14
• Overall W-L: 8-2
• Last week: 4-0
• Upcoming: vs. Knicks, vs. Bucks, vs. Raptors, at Pacers

X-Factor: Seth Curry’s shooting

No player in NBA history - not even Seth’s older brother - has shot the ball better to begin a season. Curry is en fuego, drilling over 60 percent of his 2s and 50 percent of his 3s while pumping in a career-high 17.1 points per game. He’s perhaps the biggest reason why the 76ers have the NBA’s most efficient offence as Curry’s true shooting percentage of 76.1 was the best ever through nine games.

Best True Shooting Percentage through 1st 9 games of season in 3-Pt Era (since 1979-80), minimum 10 FGA per game via @Stathead @bball_ref https://t.co/EKPDlKUGyV https://t.co/esrkXnFDXt pic.twitter.com/WWhqSEBJmz

— Mike Lynch (@SportInfo247) November 5, 2021

— Micah Adams

6. Chicago Bulls

• Previous rank: 11
• Overall W-L: 6-3
• Last week: 1-2
• Upcoming: vs. Nets, vs. Mavericks, at Warriors, at Clippers

X-Factor: Nikola Vucevic finding his feet in a new role

The Bulls’ early-season success has been carried by DeMar DeRozan and Zach LaVine, who are both top five in the league in scoring, meaning Nikola Vucevic has been the one to sacrifice touches and scoring opportunities with the big man off to one of the slowest starts in his NBA career. While he’s said he’s happy to impact the game in other ways with his passing, rebounding and screen setting, in matchups against quality big men, how Vucevic picks his moments to step up as secondary scorer will make the world of difference for the Bulls.

— Benyam Kidane

MORE: DeRozan has hit the ground running in Chicago

7. Milwaukee Bucks

• Previous rank: 1
• Overall W-L: 4-6
• Last week: 1-2
• Upcoming: at 76ers, at Knicks, at Celtics, at Hawks

X-Factor: Getting and staying healthy

Care to guess how many minutes Jrue Holiday, Khris Middleton and Giannis Antetokounmpo have played together this season? 21 , over two games. Antetokounmpo continues to do his thing — you know, putting anyone who dares stand in his way through the rim and blocking everything in sight — but an ankle injury has limited Holiday to four games and Middleton is currently in the league’s health and safety protocols. Until the three of them are on the court together again, there’s only so much we can learn about this team.

— Scott Rafferty

8. Phoenix Suns

• Previous rank: 10
• Overall W-L: 3-0
• Last week: 5-3
• Upcoming: at Kings, vs. Trail Blazers, at Grizzlies, at Rockets

X-Factor: The fallout of the Robert Sarver investigation

The Suns are dealing with issues much bigger than their on-court product. An in-depth ESPN report painted a picture of a “toxic and sometimes hostile workplace” under team owner Robert Sarver, who allegedly used racially insensitive and misogynistic language in several instances. Purely from a basketball perspective, Phoenix has great leaders in Monty Williams and Chris Paul, who has unfortunately dealt with this kind of situation before when the NBA banned former Clippers owner Donald Sterling. Still, it will be a challenge for the team to remain completely focused on hoops as this investigation unfolds.

— Jordan Greer

9. New York Knicks

• Previous rank:  9
• Overall W-L: 6-4
• Last week: 1-3
• Upcoming: at 76ers, vs. Bucks, at Hornets

X-Factor: Derrick Rose’s production

It seems clear that head coach Tom Thibodeau intends to continue to start Kemba Walker, with Rose playing a sixth man role off the bench. Walker has had more ups than downs to start the season, but there are games where he seems to disappear, such as his four-point outing against the Pacers followed by a five-point outing against the Bucks. That’s where Rose is like an ace up their sleeve, pouring in 23 points, eight boards, four assists and two steals to ignite a comeback victory over the defending champions. As long as Rose and Walker can be like a yin and yang alongside Julius Randle, RJ Barrett and Evan Fournier, the Knicks will be just fine offensively.

– Kyle Irving

10. Denver Nuggets

• Previous rank: 7
• Overall W-L: 5-4
• Last week: 1-2
• Upcoming: vs. Heat, vs. Pacers, vs. Hawks, vs. Trail Blazers

X-Factor: Michael Porter Jr. finding his touch again

Porter was recognized for the leap he made last season by finishing third in Most Improved Player voting. The scary part is that he’s still only scratching the surface of his potential , but he hasn’t exactly had a great start to this season, averaging 9.9 points on .359/.208/.556 shooting splits in Denver’s first nine games. That’s not going to cut it if the Nuggets are going to survive until Jamal Murray comes back. There’s only so much Nikola Jokic can do.

— Scott Rafferty

11. Dallas Mavericks

• Previous rank: 10
• Overall W-L: 6-3
• Last week: 2-1
• Upcoming: vs. Pelicans, at Bulls, at Spurs

X-Factor: Jalen Brunson’s secondary playmaking

There’s been a lot of chatter over the last 12 months about how the Mavericks could do with another ball handler next to Luka Doncic to take some of the playmaking duties off of his plate. Maybe more Brunson is the answer? In his first start of the season, Brunson scored 25 points. He followed it up by dropping 31 points on the Spurs, making bucket after bucket down the stretch. He’s probably not going to continue averaging 28.0 points per game as a starter, but him taking another leap would be a pretty big deal.

— Scott Rafferty

MORE: Doncic stuns Celtics with buzzer-beating game-winner

12. Los Angeles Lakers

• Previous rank : 5
• Overall W-L: 5-5
• Last week: 1-2
• Upcoming: vs. Hornets, vs. Heat, vs. Timberwolves, vs. Spurs

X-Factor: Health

OK, so maybe this is a cop-out. And there is no denying that you could write “health” for all 30 teams. But it feels especially important for the Lakers who are already banged up after entering this season as one of the oldest teams in NBA history. LeBron James is out with an abdominal strain, Anthony Davis sustained a thumb injury in Thursday’s loss to the Thunder, Talen Horton-Tucker is still recovering from surgery on his thumb, and Trevor Ariza likely won’t make his Lakers’ debut until December as he recovers from ankle surgery.

— Micah Adams

13. Toronto Raptors

• Previous rank: 21
• Overall W-L: 6-5
• Last week: 2-2
• Upcoming: at Celtics, at 76ers, vs. Pistons

X-Factor: Scottie Barnes’ offence

The rap sheet on Barnes coming out of Florida State was that he showed immense promise as a wing defender but only if he could shore up an incredibly limited offensive game enough to stay on the floor. So naturally, the supposedly offensively challenged Barnes leads all rookies in scoring at 16.6 points per game, which would be the most by a Raptors rookie since Vince Carter in 1998-99. If the rookie’s offensive exploits are for real, Toronto may have unearthed yet another draft gem.

— Micah Adams

MORE: KD impressed by Barnes' play

14. Atlanta Hawks

• Previous rank: 8
• Overall W-L: 1-3
• Last week: 4-6
• Upcoming: at Warriors, at Jazz, at Nuggets, vs. Bucks

X-Factor: Staying focused during the “boring” regular season

Trae Young raised some eyebrows when he called the regular season “boring” and said that you have to “find the motivation to play like the playoffs.” The Hawks have a deep roster full of talented players, yet they find themselves near the bottom of the Eastern Conference standings to start the season. Atlanta coach Nate McMillan wants to see his squad show that it is “hungry” to be better than it was last year. A tough stretch of games this week could be a good indicator of whether the Hawks heard the message.

— Jordan Greer

15. Memphis Grizzlies

• Previous rank: 16
• Overall W-L: 2-1
• Last week: 5-4
• Upcoming: vs. Timberwolves, vs. Hornets, vs. Suns, at Pelicans

X-Factor: Jaren Jackson Jr. finding his rhythm

Coming back from injury this season, Jackson Jr. was earmarked as the team’s second star alongside Ja Morant, but it’s been the electric point guard carrying the Grizzlies early on. Jackson Jr. has the potential to raise the team’s ceiling to a genuine playoff threat, but his poor shooting (34.2 percent from the field, 33.3 percent from 3) and consistent foul trouble has so far limited his impact in games, especially in the minutes he’s on court without Morant. As the only big man in the rotation who can space the floor, his ability to knock down shots and open up even more space for Morant is arguably their biggest key to success this season.

— Benyam Kidane

16. Washington Wizards

• Previous rank:  15
• Overall W-L: 7-3
• Last week: 2-2
• Upcoming:  at Cavaliers, at Magic

X-Factor:  Kyle Kuzma's rebounding

It's still early in the season, but Kuzma is averaging over nine boards, which is the highest mark of his career … by far. He's already turned in games of 11, 12, 15 and 17 rebounds this season, and there are over 70 games remaining. Prior to this season, the most rebounds Kuzma had averaged was 6.3 during his rookie campaign. This season, Kuzma's activity on the boards has played a big role in Washington ranking among the league's top five teams in rebounds per game , putting its name among teams like Miami, Golden State and Utah, each of whom landed in the top five of this week's rankings.

— Gilbert McGregor

17. Portland Trail Blazers

• Previous rank: 13
• Overall W-L: 2-2
• Last week: 5-5
• Upcoming: at Clippers, at Suns, at Rockets, at Nuggets

X-Factor: When will Damian Lillard start heating up?

10 games into the season, Lillard has yet to find his shooting stroke. He isn’t just performing below his usual All-Star standards — his numbers are flat-out bad. He is shooting less than 40 percent from the field and 30 percent from 3-point range. Does this mean the Trail Blazers should panic? No, of course not. Lillard can get hot at any time. Until he does, though, they will struggle to consistently win games.

— Jordan Greer

18. Boston Celtics

• Previous rank: 18
• Overall W-L: 2-2
• Last week: 4-6
• Upcoming: vs. Raptors, vs. Bucks, at Cavaliers

X-factor: Al Horford turning back the clock.

With the noise coming out of Boston to start the season, all the attention has been on Marcus Smart’s comments and the All-Star tandem of Jayson Tatum and Jaylen Brown. Meanwhile, offseason acquisition Horford has been by far the team’s most consistent player, looking like the version of himself the Celtics signed back in the summer of 2016. Averaging 13.5 points, 9.4 rebounds, 3.3 assists and 2.6 blocks per game, Boston is getting more production out of the 35-year-old veteran than anyone could have imagined.

– Kyle Irving

MORE: Are the Celtics as bad as their start suggests?

19. LA Clippers

• Previous rank: 20
• Overall W-L: 5-4
• Last week: 4-0
• Upcoming: vs. Trail Blazers, vs. Heat, vs. Timberwolves, vs. Bulls

X-Factor: Players playing up to their contracts

Paul George has been playing at an MVP level to start the season, but without Kawhi Leonard, the Clippers have struggled to churn out wins. LA paid five role players handsomely over the last two offseasons, with Luke Kennard and Marcus Morris Sr. each signing a four-year, $64 million deal, Reggie Jackson and Terance Mann each signing a two-year, $22 million deal, and Serge Ibaka signing a two-year, $19 million deal.

Thus far, their production hasn’t exactly matched their value. Morris has been out with a knee injury, as has Ibaka with a back injury. Jackson, Mann and Kennard have all had good games, but nothing consistent to this point. If the Clippers are going to win without Kawhi, they’ll need those five players to get going.

– Kyle Irving

20. Cleveland Cavaliers

• Previous rank:  23
• Overall W-L: 7-4
• Last week: 4-0
• Upcoming:  vs. Wizards, vs. Pistons, vs. Celtics

X-Factor:  Darius Garland's playmaking

Who says Garland can't be the floor general for a successful team? Three weeks into his third NBA season, Garland is among the league leaders in assists per game, placing his name alongside the likes of Russell Westbrook, James Harden, Trae Young and Chris Paul. Garland's incremental progress as a playmaker has allowed him to grow into a player that is averaging nearly eight assists per night, setting the table for a number of his talented Cavs teammates. If it's a sign of things to come, Cleveland has even more winning in its future.

— Gilbert McGregor

21. Sacramento Kings

• Previous rank:  22
• Overall W-L: 5-5
• Last week: 2-2
• Upcoming: vs. Suns, at Spurs, at Thunder

X-Factor:  The 3 ball

In a 140-110 rout over the Hornets, the Kings set a new franchise record with 22 made 3-pointers, doing so at a 50 percent clip. It starts with Buddy Hield, who is among the league leaders in total made 3-pointers and 3s per game, which is especially impressive given the fact that he's doing so as a reserve. Sacramento is far from the top of the league with respect to 3-point shooting, but with an elite shooter like Hield in the fold, the 3 can make a difference on any given night.

— Gilbert McGregor

22. Charlotte Hornets

• Previous rank:  17
• Overall W-L: 5-6
• Last week: 0-4
• Upcoming: at Lakers, at Grizzlies, vs. Knicks, vs. Warriors

X-Factor: Terry Rozier’s re-emergence

It’s impressive that the Hornets got off to the start they did this season despite Rozier’s struggles. Remember, Rozier is coming off of a career year in which he led Charlotte in scoring with 20.4 points per game and was one of the league’s best performers in the clutch. He’s still working his way back from the ankle injury he suffered in preseason, but when he finds his rhythm again, it’ll add even more juice to the Hornets.

— Scott Rafferty

23. Minnesota Timberwolves

• Previous rank: 19
• Overall W-L: 3-5
• Last week: 0-3
• Upcoming: at Grizzlies, at Warriors, at Lakers, at Clippers

X-Factor: More Towns touches

Karl-Anthony Towns is averaging 23.4 points and within shouting distance of 50/40/90 shooting splits (field goals/3-pointers/free throws). There are not many big men that can match up with him given his ability to score at every level. So why is he third on his team in usage percentage behind Anthony Edwards and D’Angelo Russell, both of whom are far less efficient than Towns? If the Timberwolves happened to be an offensive juggernaut, maybe you could let that slide, but they have one of the worst offensive ratings in the league.

— Jordan Greer

24. Indiana Pacers

• Previous rank:  25
• Overall W-L: 4-7
• Last week: 3-1
• Upcoming:  at Nuggets, at Jazz, vs. 76ers

X-Factor:  The presence of Chris Duarte

Duarte, 24, is much older than the typical lottery pick, but he approaches the game with a certain calmness that is most certainly a product of maturity. The rookie's ability to score efficiently from the onset of his career has been a huge development for an Indiana team that began the season without one wing scorer in Caris LeVert and still anxiously awaits the return of another prolific player in TJ Warren.

Duarte is getting invaluable experience early on and things should only get easier for him as he continues to adjust to the NBA game and the Pacers get more weapons back.

— Gilbert McGregor

25. San Antonio Spurs

• Previous rank: 24
• Overall W-L: 3-7
• Last week: 1-3
• Upcoming: vs. Kings, vs. Mavericks, at Lakers

X-Factor: Derrick White stepping up offensively

White has been fantastic defensively and distributing the ball, second on the team in assists behind Dejounte Murray — who is having a breakout campaign — but with the Spurs losing several close games this season, they’ve needed that secondary offensive punch with many expecting that to be White. He has immense two-way potential, however, he is currently fourth in points per game behind Murray, Keldon Johnson and Jakob Poeltl. If his offence catches up to his defence, the Spurs will be in a much better position.

— Benyam Kidane

26. Houston Rockets

• Previous rank:  28
• Overall W-L: 1-9
• Last week: 0-4
• Upcoming: vs. Pistons, vs. Trail Blazers, vs. Suns

X-Factor:  Embracing adversity

A tip of the hat to Christian Wood for the words here, but they could not reign more true.

Embrace adversity .

— Christian Wood (@Chriswood_5) November 7, 2021

As expected, Wood is posting impressive averages to open the season, but Houston isn't experiencing much team success. As young as this Rockets team is, these losses — especially the close ones — are the ugly part of the process. With young players like Jalen Green, Kevin Porter Jr., Usman Garuba and Alperen Sengun carrying the torch for the future, the adversity they make it through now will make for success in the years to come.

— Gilbert McGregor

27. Oklahoma City Thunder

• Previous rank: 27
• Overall W-L: 3-6
• Last week: 2-1
• Upcoming: at Pelicans, vs. Kings, vs. Nets

X-Factor: Josh Giddey’s playmaking

It seems obvious, but the Thunder look extremely dangerous when the rookie is in his passing groove. The 19-year-old’s ability to generate easy looks at the rim for his teammates is impressive for his age/experience, and in their first two wins of the season — both against the Lakers — Giddey has combined for 18 assists. When he’s firing off passes and controlling the offence, it opens up a ton of opportunity for Shai Gilgeous-Alexander to focus on scoring, which he’s doing at an elite level this season.

— Benyam Kidane

28. Orlando Magic

• Previous rank : 29
• Overall W-L: 3-8
• Last week: 2-2
• Upcoming: vs. Nets, vs. Wizards

X-Factor: Cole Anthony taking over

The No. 15 pick in the 2020 NBA Draft, Anthony has hit the ground running this season. In his third game of the season, he exploded for 29 points, 16 rebounds and eight assists. Since then, he’s scored 20-plus points five times, including a season-best 33 points in Orlando’s win over Utah. It’s been a rough start to the season for the Magic, but Anthony’s play has been a bright spot.

— Scott Rafferty

29. New Orleans Pelicans

• Previous rank: 26
• Overall W-L: 0-3
• Last week: 1-9
• Upcoming: at Mavericks, vs. Thunder, vs. Nets, vs. Grizzlies

X-Factor: Zion Williamson’s health

Williamson set the league on fire last season, averaging 27.0 points per game on 61.1 percent shooting from the field. In less than 100 career games, he’s proven himself to be one of the most dominant and unique talents we’ve seen in a long time. The problem? He can’t seem to stay healthy. He appeared in 61 of a possible 72 games last season but was limited to 24 games in his rookie season and is still at least two weeks away from making his debut this season. Without him, the Pelicans are going to have a hard time winning games.

— Scott Rafferty

30. Detroit Pistons

• Previous rank: 30
• Overall W-L: 1-8
• Last week: 0-3
• Upcoming: at Rockets, at Cavaliers, at Raptors

X-Factor: Being patient

Particularly when it comes to Cade Cunningham, who, need you be reminded, is a rookie working his way back from an ankle injury he suffered in training camp. His shot isn’t falling right now — he went 7-for-39 (17.9 percent) from the field in his first three games — but Cunningham has shown off other parts of his game to get excited about, like his court vision and defensive versatility. The rest will eventually fall into place.

— Scott Rafferty

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