Just about a quarter of the way into the 2019-20 NBA season, and the Los Angeles Lakers and Milwaukee Bucks appear to be a step ahead of the competition. Behind the stellar individual play of Giannis Antetokounmpo, LeBron James and Anthony Davis, those two teams are the class of the league right now by pretty much every metric. But that doesn't mean it will stay that way.

Just this week we've seen two teams -- the Miami Heat and Boston Celtics -- assert themselves as worthy contenders by taking down some of the league's best adversaries. Jimmy Butler has been phenomenal, while Jaylen Brown has taken the step forward that most expected to see from the explosive wing last season. Both teams moved up in this week's Power Rankings, while the Bucks narrowly edged out the Lakers for the top spot.

Biggest Movers
6 Celtics
7 Raptors
1 Bucks The Bucks put an exclamation point on another undefeated week by absolutely throttling the Clippers in Milwaukee on Friday night. This was a statement win of the highest order, and the hottest team in the league has now won 14 straight games. They're in the top two in both offensive and defensive efficiency, which simply doesn't happen. The Bucks earned their No. 1 spot once again. -- 54-21
2 Lakers After hearing cries about their "soft" schedule, the Lakers silenced that talk by picking up huge road wins in Denver and Utah to start the week, then another one in Portland before heading home to take care of the Timberwolves. The Lakers are starting to generate some well-deserved MVP buzz for Anthony Davis, and they've managed to keep rolling despite relatively minimal contributions from Kyle Kuzma. If he can get better offensively, it could take the Lakers to an even higher level. 1 37-38
3 Celtics The Celtics picked up home wins over the Heat and Nuggets this week, and looked impressive in the process. Jaylen Brown averaged 26 points per game in the two wins to go along with the steady play of Kemba Walker and Jayson Tatum. More good news for the Celtics: Marcus Smart looked healthy in his return on Friday, and Gordon Hayward may take the court on Monday. 6 52-24
4 Heat Miami is rolling and Jimmy Butler is a bad man -- just ask him. He absolutely took over in an overtime win over the Raptors, scored 37 points in a loss to Boston the next night, then put up another triple-double as he helped save the Heat from a potentially disastrous home loss to the Wizards. They needed overtime to beat the Bulls, but Tyler Herro appears to be out of his mini shooting slump. The Heat are legit. 4 40-36
5 Clippers The Clippers went 2-1 this week ... but the one loss was a big one. They were blown off the court by Giannis Antetokounmpo and the Bucks, displaying that the Clippers have a long way to go before they reach their full potential. The beauty of this team is that they don't seem too concerned with regular-season wins, and they'll keep fine-tuning until the postseason, even if that means possibly missing out on a No. 1 seed. 1 40-36
6 Mavericks The Mavs won six straight after their blowout loss to the Clippers before dropping a tough one at home to the Kings on Sunday. Luka Doncic passed Michael Jordan with his streak of consecutive 25-5-5 games, as he continues to figure out ways to win even when he's not at his peak offensively. Is Dallas' success sustainable? We'll find out. But right now it's at the top of the league. 1 37-39
7 76ers The Sixers looked great this week outside of a perplexing loss to the Wizards on Thursday. Ben Simmons went for a career-high 34 points in a drubbing of the Cavs, and he confidently knocked down his second 3-pointer of the season. The fact that Simmons' best game of the season came with Joel Embiid on the sidelines certainly raises some familiar eyebrows, and the team managed to beat Toronto on Sunday despite a subpar game from Embiid. 1 49-26
8 Rockets The Rockets went 2-1 this week, but if you ask them, they were undefeated. James Harden's dunk was counted as a miss instead of a make, and Houston went on to lose to the Spurs in double-overtime on Tuesday. It bounced back nicely, however, picking up a road win over the Raptors before beating the Suns at home. Ben McLemore has been tremendous, picking up the slack in games where Harden has failed to put up huge scoring numbers. 2 18-58
9 Raptors Toronto suffered tough losses to the Heat and Rockets at home to start the week before dropping a road game to the 76ers on Sunday, as Kyle Lowry re-entered the fold. The Raptors aren't a worse team with Lowry, but they had things clicking so well without him that there would inevitably be a period of adjustment. They're still one of the top teams in the league in net rating, so a subpar week is no cause for panic. 7 38-38
10 Nuggets Denver failed a big test by losing to the Lakers at home, then later fell to the Celtics and Nets as well. The Nuggets are a very good team, there's no doubt about that, but as of now their ceiling doesn't appear quite as high as the rest of the NBA elite. It will be interesting to see if they seek out another piece once more trade options open on Dec. 15. 3 51-24
11 Pacers The Pacers rarely blow teams out, but they just figure out a way to get wins. They barely hung on to beat the Knicks on Saturday to cap off a 3-1 week, as six players averaged double-digit scoring over those four games, led by TJ Warren's 22.3 on 47 percent 3-point shooting. -- 33-43
12 Nets Kyrie Irving looks to be a ways out from a return to the court, and Nets fans aren't complaining. They've been hot since Irving went down with a shoulder injury, with Spencer Dinwiddie, Garrett Temple, Taurean Prince and Joe Harris relishing the extra opportunity with Caris LeVert also sidelined. The 1-2 punch of Jarrett Allen and DeAndre Jordan has also been effective in the middle. 1 40-35
13 Jazz After losses to the 76ers and Lakers, Utah snapped a three-game skid by beating the Grizzlies at home. The Jazz's net rating is now approaching zero, as their normally stout defense has allowed 114.2 points per 100 possessions over the last four games -- 23rd in the NBA over that span. After a solid start, the Jazz have slipped considerably. 1 35-40
14 Magic A four-game winning streak has brought the Magic back to .500 for the first time since they started the season 2-2. They haven't beaten the best competition recently, but they've done it without Nikola Vucevic. A few games against suspect defenses may have been exactly what this team needed to get going offensively. 3 32-44
15 Thunder The Thunder had a good week with wins over the Timberwolves and Blazers following a loss to the Pacers. Steven Adams nearly averaged a double-double for the week, while Dennis Schroder has been on a scoring tear, averaging 21.3 points on 55 percent 3-point shooting over his last three games. -- 37-39
16 Spurs It took three extra periods, but the Spurs got two much-needed wins this week. Say what you will about James Harden's dunk not counting, but Lonnie Walker had a breakout game as he brought the Spurs back late against the Rockets. At this point, it's just good for San Antonio to get some positive momentum, no matter how the wins come. 6 19-56
17 Kings Go figure. The Kings lose to three very beatable teams -- the Bulls, Blazers and Spurs -- then turn around and beat the red-hot Mavericks in Dallas. Marvin Bagley is nearing a return, so it will be interesting to see how that affects the Kings moving forward, especially since Richaun Holmes and Nemanja Bjelica have done an admirable job with the extra minutes. 1 45-30
18 Timberwolves It was a rough week for the Wolves, who lost to the Thunder in epic fashion following a delay of game, an accidentally made free throw by Karl-Anthony Towns, and a Steven Adams full-court inbound pass that found Dennis Schroder in stride to force overtime. Their other two losses were to the Mavs and Lakers, two of the league's hottest teams, but still not the direction the team was hoping to trend. 4 39-37
19 Suns The Suns went 1-2 this week, and their win wasn't exactly impressive -- beating the Pelicans in overtime. The defense that helped spark the Suns' hot start has mostly abandoned them, and the extended absence of Aron Baynes hasn't helped matters. -- 40-35
20 Trail Blazers The Carmelo Anthony renaissance couldn't carry the Blazers through a rough week, as they dropped three of four. Anthony came back down to earth after earning Western Conference Player of the Week honors, averaging just 13.3 points on 32 percent shooting for the week. Rodney Hood's torn Achilles further depletes an already thin frontcourt. 2 32-43
21 Pistons The Pistons picked up wins over the Cavs and Pacers this week, with a blowout loss to the Bucks in between. Blake Griffin looks like he's starting to get his legs underneath him, and Andre Drummond averaged nearly 22 points and 17 rebounds for the week. -- 16-59
22 Bulls The Bulls were on their way to a solid week after winning consecutive games for the first time all season, including a big road victory over the Kings. But then they went ahead and lost to the Warriors ... again. Zach LaVine's attempt at hero ball on the potential game-winner clanked off the back iron, then Chicago followed that up with an overtime loss in Miami. It was quite literally two steps forward, two steps back for the Bulls this week. 6 36-39
23 Wizards An injury to Thomas Bryant decimated the Wizards' thin frontcourt, as Moe Wagner is now getting all the run he can handle and Ian Mahinmi has suddenly resurfaced. Washington continues to play league-worst defense while pushing the tempo offensively, which at least leads to some entertaining losses. -- 34-42
24 Hawks The Hawks got back the taste of winning for the first time in a long time by beating the Warriors and Hornets this week. Neither is exactly the '86 Celtics, but Atlanta sorely needed to get back in the win column after a 10-game losing streak. Kevin Huerter is getting healthy, which will greatly help the offense. 6 38-38
25 Hornets The Hornets beat one of the worst teams in the league on Wednesday (the Warriors), then lost to one of the worst teams in the league on Sunday (the Hawks). Devonte' Graham continues to be one of the lone bright spots for Charlotte this season, as he tied a franchise record by making 10 3-pointers in the win over Golden State. 5 26-51
26 Pelicans The Pels were blown out twice by the Mavericks this week, with an overtime loss to the Suns sandwiched in-between. It's been a rough go all season for New Orleans, as the team simply cannot figure out a way to stop its opponent from scoring. Zion Williamson will fix some of their problems if he returns healthy, but the Pelicans still have a long way to go. 1 38-38
27 Warriors That's two straight weeks with a win for the Warriors (both over the Bulls), but they also had bad losses to the Hawks and Hornets on the road this week. The defense continues to improve, but the offense has taken a nosedive despite the return of D'Angelo Russell. -- 40-37
28 Grizzlies The loss of Ja Morant has not been kind to the Grizzlies, as they dropped all three games this week. Jaren Jackson Jr. has looked confident taking on more of the offensive load with Morant out, while Jonas Valanciunas has continued to be a force on the inside. Grayson Allen has also benefited from the extra playing time, averaging 11 points on 46 percent 3-point shooting since Morant's injury. 4 48-27
29 Cavaliers This was not a pretty week for the Cavaliers, who got stomped by nearly 50 points against the 76ers on Saturday. There are rumors that Cleveland is now listening to offers for Kevin Love, something it likely has been doing all season long, and Tristan Thompson is performing well enough on an expiring contract to draw some interest as well. On the court, it looks like it's going to be ugly in Cleveland for the foreseeable future. 3 48-29
30 Knicks Blowout losses to the Bucks and Nuggets led to the firing of David Fizdale, and the Knicks were inches away from possibly winning their first game without him. But Julius Randle's potentially overtime-forcing free throw clanked off the iron, and the Knicks lost their ninth straight. To say things are bleak in New York right now would be the understatement of the year. 1 43-33