No, this isn't the 1980s. Or the late 2000s. But yes, the Boston Celtics and Los Angeles Lakers are back atop the NBA power structure three weeks into the 2019-20 season. Once bitter rivals, the Celtics and Lakers are the top teams in the Eastern and Western Conferences this week, respectively.

The Celtics haven't lost since opening night, while the Lakers rattled off seven straight wins before losing to the shorthanded Raptors on Sunday night. Speaking of Toronto, it just keeps churning out wins and finds itself one of the league's five seven-win teams, along with the Celtics, Lakers, Bucks and Nuggets. As for the Bucks, Giannis Antetokounmpo is putting up insane numbers to almost single-handedly keep his team winning.

Now would be a good time to remind everyone that these rankings reflect the best teams in the league right now, and vary from week to week based on recent performance. Here are this week's NBA Power Rankings.

Biggest Movers
8 Raptors
9 76ers
1 Celtics Boston ran its winning streak to seven games this week, but it came at a cost. Gordon Hayward, who appeared to have returned to his old form this season, suffered a broken hand against the Spurs. It's a big loss for the Celtics, but their depth should allow the success to continue. Kemba Walker has been as advertised, while Jayson Tatum and Jaylen Brown will have to step up as playmakers in Hayward's absence. 4 64-18
2 Raptors Hey, remember when losing Kawhi Leonard was supposed to mean a huge step backwards for Toronto? Yeah, that's not happening. The Raptors are now tied for the league lead in wins after a 3-0 week capped off by a gigantic road win over the Lakers without Kyle Lowry and Serge Ibaka. Pascal Siakam and OG Anunoby have been fantastic this season, and the "next man up" mentality has trickled all the way down to the likes of Chris Boucher and Terence Davis with the recent injuries. Nick Nurse and the Raptors are for real, and are dangerous no matter who they put on the court. 8 25-57
3 Lakers The Lakers were poised to be this week's top team before blowing an 11-point lead to the shorthanded Raptors (no Lowry or Ibaka) at home. Los Angeles went ice cold in the third quarter and couldn't get stops down the stretch, but that doesn't negate the seven-game winning streak that preceded the loss. They're still the second-best defense in the NBA, but this roster can't afford a 5-for-15 night from LeBron against a good team. 1 47-35
4 Bucks A last-second loss to the Jazz in Utah was the only blemish for the Bucks this week, as Giannis Antetokounmpo has now recorded at least 30 points and 13 rebounds in five straight games. Milwaukee has the second-best net rating in the league and still looks like it's not quite clicking on all cylinders. Once they figure some things out, they'll be truly scary. 2 49-33
5 Clippers The cloud of "load management" has shrouded the Clippers' early success this season, and they've still only lost one game with Kawhi Leonard in the lineup. It would have been nice to see him match up with Giannis Antetokounmpo, but Kawhi showed once again what a killer he is by scoring 18 points in the fourth quarter to beat the Blazers the following night. The Clippers could become the league's top team with the return of Paul George imminent. 1 51-31
6 Nuggets Denver picked up its first double-digit win of the season over the Heat, then got back to its nail-biting ways by beating the 76ers and Timberwolves by a combined five points. While the other seven-win teams all have season point differentials over seven, the Nuggets have only outscored opponents by three. Nikola Jokic hasn't looked like himself, so it's a testament to the team that they've been able to pull out wins despite not playing to their full capability. 6 57-25
7 Jazz Utah picked up close home wins over the 76ers and Bucks, two of the Eastern Conference's best teams. Bojan Bogdanovic scored 33 points in the win over the Bucks, including the game-winner at the buzzer, and Mike Conley added five 3-pointers. Meanwhile, the defense just continues to suffocate opponents. 6 31-51
8 Mavericks Luka Doncic looks like an MVP candidate as a 20-year-old, but the Mavs inexplicably lost to the Knicks at home this week. Young teams will occasionally have slip-ups, but that's unacceptable for a squad looking to make the playoffs in the rough West. Overall the Mavericks have looked good, though, which is great news for them considering Kristaps Porzingis hasn't yet gotten his footing. 1 50-32
9 Suns Is it safe to say the Suns are for real? Despite a home loss to the Heat, Phoenix continues to impress with Devin Booker averaging nearly 30 points on an absurd 67 percent field goals and 69 percent 3-pointers over the last three games. The defense slipped this week, which could be cause for concern, but they scored enough to make up for it. The Suns look like a genuine contender for a playoff spot. 1 49-33
10 76ers The Sixers didn't remain the NBA's lone unbeaten team for long, as Joel Embiid's suspension and Ben Simmons' shoulder injury contributed to three consecutive road losses to strong teams in the Suns, Jazz and Nuggets. The 76ers' depth was already an issue, so the loss of Simmons hurts on both ends, though Raul Neto and Trey Burke have performed admirably in his absence. We'll have to wait and see how long Simmons is out, but when he's healthy the Sixers are still one of the league's top teams. 9 47-35
11 Heat The Heat had three tough road games this week (Nuggets, Suns, Lakers) and dropped two of them. Their pace has slowed considerably since the return of Jimmy Butler, and fell even lower this week. Losses to the Nuggets and Lakers are hardly egregious and the win over the Suns was impressive, so the Heat remain in the mix at the top of the East for now. 8 46-36
12 Rockets After a rough start, the Rockets rattled off three straight wins over teams they should beat -- the Grizzlies, Warriors and Bulls. James Harden found his shooting stroke after early struggles, averaging nearly 41 points over the three wins while shooting 43 percent from deep. Houston cranked up the defense this week, but we'll see if it lasts against better quality opponents. 4 41-41
13 Pacers Indiana followed an overtime loss to the Hornets with wins over the Wizards, Pistons and Magic. Domantas Sabonis has been a double-double machine in the absence of Myles Turner, who is getting closer to a return. The Pacers were also without Jeremy Lamb, who has become one of their main offensive options, for most of the week. They've suffered through injury problems, but still have a top-10 net rating -- pretty impressive. 1 47-35
14 Nets Brooklyn beat the struggling Pelicans and Blazers before getting blown out by the Suns in Phoenix to close out the week. The defense has been awful and is a real concern for Kenny Atkinson, but Kyrie Irving, Caris LeVert and Spencer Dinwiddie have produced enough offense to keep the Nets in games. 4 32-50
15 Spurs San Antonio had no answer for Trae Young in a loss to the John Collins-less Hawks, but followed that up with a home win over the Thunder. They closed out the week with a blowout loss to the red-hot Celtics. The Spurs' porous defense from last season reared its ugly head this week, and they now sit in the bottom half of the league. Dejounte Murray's performance has been a solid litmus test for San Antonio's success so far -- he's averaging over 15 points and seven assists in wins, while putting up just 8.3 points and 3.5 assists in losses. 4 22-60
16 Timberwolves It was a rough week for the Wolves, who lost to the Bucks, Grizzlies and Nuggets, with an overtime win over the Warriors mixed in. The late-game balance between Andrew Wiggins and Karl-Anthony Towns seemed a bit off in back-to-back overtime games to close out the week, as the Timberwolves have struggled after a strong start to the season. 7 56-26
17 Thunder The Thunder have been pretty much what we thought they were. They don't get blown out, but they consistently lose to good teams. Shai Gilgeous-Alexander has been a bright spot and looks like a real piece to build around moving forward, but this team has .500 (or slightly worse) written all over it. 2 57-25
18 Cavaliers The Cavs are a bad team, but so far they've proven that they can at least beat other bad teams. This week it was the Wizards and Knicks, as Tristan Thompson continues to turn back the clock with perpetual double-doubles. Collin Sexton still isn't getting his teammates involved as much as the Cavs would like, but he's averaged 22.7 points over his last three games while making 9-of-16 3-pointers. 6 48-34
19 Trail Blazers An overtime win over the Hawks saved what would have been a winless week for the Blazers, who are reeling since Zach Collins' injury. Terry Stotts has yet to find a consistent rotation that works, and CJ McCollum has struggled shooting the ball (39 percent field goals, 31 percent 3-pointers). If the Blazers have taught us anything over the years, it's never to count them out, but they're not playing well right now at all. 4 21-61
20 Kings The Kings played the Raptors close in Toronto and then took care of the Hawks, and it appears the early-season offensive struggles are a thing of the past -- Sacramento has averaged over 121 points per 100 possessions during its last three games. Next up: Fixing the defense. 3 46-36
21 Hawks Trae Young returned from an ankle injury to lead the Hawks to a win over the Spurs, but things went downhill from there with losses to the Bulls, Kings and Blazers. Jabari Parker has stepped up offensively with John Collins suspended, but they simply haven't been able to put enough points on the board to get wins given the type of defense that they play. 1 36-46
22 Hornets Charlotte beat the Pacers in overtime before losing to the Celtics, Pelicans and 76ers. Devonte' Graham has been fantastic early, and PJ Washington continues his strong rookie campaign, but offense has been a struggle for the Hornets. We knew it was going to be a slog, so sitting at 4-6 after 10 games is actually better than most expected. 1 21-61
23 Pistons Andre Drummond continues to put up gaudy stats and Luke Kennard and Bruce Brown have looked good with extra opportunity due to the absence of Reggie Jackson and Derrick Rose, but that's about all Detroit has going right now. They got blown out by the Wizards (never a good thing) before beating the Kincks and losing to the Pacers, who it seems like they've played about 14 times already this season. The good news is, Blake Griffin is set to return to the lineup soon. 6 14-68
24 Magic Time to panic in Orlando? The Magic have failed to build off the success of last season, going 1-3 this week despite breaking the 100-point threshold in three consecutive games, after failing to do it in their first seven. The offense is just slightly better than the league-worst Knicks, which has prevented them from winning games despite their stout defense. They're last in the league in 3-point shooting at 28.2 percent. 2 47-35
25 Bulls It looked like the Bulls were going to turn their season around with a big win over the Lakers ... then they blew a 19-point second-half lead because, well, they're the Bulls. The main problem has been offense, stemming from subpar seasons from Zach LaVine and Lauri Markkanen so far. Not much has gone right for Chicago, and it's hard to see a light at the end of the tunnel. -- 39-43
26 Wizards The Wizards beat the Pistons before losing to the Pacers and then the Cavs in one of their few national TV showcases. They're scoring at a decent clip but the defense is atrocious, to be expected from a young team that's now starting Isaiah Thomas. Bradley Beal's shooting has fallen off, likely a product of defenses loading up to stop him. That's not going to change any time soon, and the Wizards will struggle to find other sources of production. -- 15-67
27 Pelicans The Pelicans' disappointing season continues, as they simply can't find a way to get stops despite having pretty strong individual defenders. Brandon Ingram continues to be tremendous offensively, but Jrue Holiday has yet to find his footing on that end of the court. JJ Redick had a breakout game in a win over the Hornets after struggling for most of the season, so that could be a step in the right direction. But if the Pels are going to win, it's going to have to start with defense. -- 49-33
28 Warriors Led by Eric Paschall and "MVP" chants from the crowd, the Warriors improbably picked up their first-ever win at Chase Center against the Blazers, before losing all three games of their road trip. D'Angelo Russell dropped 52 points in an overtime loss to the Timberwolves, then followed it up with 30 against the Thunder. He'll be the main source of offense while Steph Curry and Klay Thompson remain sidelined, and it likely won't translate to many wins given the Warriors' league-worst defense. 1 46-36
29 Knicks Just when you think the Knicks are a lost cause, they go out and beat Luka Doncic, Kristaps Porzingis and the Mavericks on the road. The celebration was short-lived, however, as they returned home to get pounded by the Cavs on Sunday. New York has the worst offense in the NBA and is tied with the Grizzlies for worst net rating. This is a bad team, but at least Frank Ntilikina showed some signs of life with Elfrid Payton and Dennis Smith Jr. out of the lineup. 1 50-32
30 Grizzlies Ja Morant might be the leading candidate for Rookie of the Year, but Jaren Jackson has yet to get things going in his sophomore season because he simply can't stay on the court. He's averaging over four fouls per game in just over 25 minutes. Until Jackson learns to control himself when it comes to fouls (a problem he had last year as well), it's going to decelerate his growth by limiting his minutes. -- 27-55