This first appeared in the Nov. 6 edition of The Washington Post’s NBA newsletter, The Monday Morning Post Up. You can subscribe by clicking here.

Monday marks the start of the fourth week of the NBA season, enough time to begin seeing trends around the league.

One focuses on a handful of teams outpacing preseason projections through their first 10 games, looking like they have a chance to prove their doubters wrong over the course of the next few months.

But will they? Or is the success experienced by those teams only fleeting, and likely to regress?

That’s what we’ll attempt to decipher, as we look at the five most surprising teams in the NBA in an attempt to decide whether their play can last or is a case of playing above their heads.

1. Boston Celtics

Unlike every other team on this list, the Celtics came into this season with sky-high expectations … only to see Gordon Hayward suffer a gruesome injury six minutes into the season. In the span of about 26 hours, the Celtics went from a team that looked like a potential threat to dethrone Cleveland atop the East to being 0-2 and without its best player.

But, remarkably, the Celtics rebounded to win their next eight games, including Sunday’s 104-88 victory over the Orlando Magic, giving them the NBA’s best record at 8-2. Even more remarkably, Boston has the NBA’s best defense, allowing an absurdly low 94.7 points per 100 possessions — a full 2.5 points fewer than the second-place Oklahoma City Thunder.

Considering Boston’s biggest question coming into the season was how good it would be defensively without Avery Bradley and Jae Crowder (and then Hayward, an excellent defender, as well), having the league’s best defense seems entirely unsustainable. If it drops off, will the fact that the team’s two young starting forwards, second-year man Jaylen Brown and rookie Jayson Tatum, have been excellent thus far, while Kyrie Irving and Al Horford have created instant pick-and-roll chemistry, be enough to offset that?

If the Celtics can keep Irving and Horford healthy, and the defense doesn’t drop off a cliff (meaning it winds up somewhere between, say, 10th and 15th overall), Boston should be able to remain near the top of the Eastern Conference — an impressive achievement given the shock of Hayward’s injury. It would also be yet another credit to Brad Stevens, who is once again earning his reputation as one of the NBA’s best coaches.

Likelihood of sustaining: 8 out of 10

2. Detroit Pistons

Two years ago, the Pistons were a young, up-and-coming team that won 44 games and seemed poised to make a move up the Eastern Conference standings. But last season, Detroit saw virtually everything go wrong and spent the year dealing with trade rumors about every player on the team while winning 37 games.

The Pistons came into this season as one of the league’s most boring teams, as well as one of the hardest to judge. Would they return to where they were two years ago? Or would they disappoint, leaving open the possibility of wholesale changes?

So far, it seems like the former. Detroit is now 7-3 after wins over the Milwaukee Bucks Friday and Sacramento Kings Saturday, and is on the verge of having both a top 10 offense and defense. Reggie Jackson looks like he’s back to something close to the near all-star he was two years ago, while Andre Drummond has also rebounded. And, as anyone around the Pistons will openly tell you, how those two fare will determine just how good Detroit will be.

It also should be noted that the offseason upgrade from Kentavious Caldwell-Pope to Avery Bradley was undersold, and Bradley’s 42 percent shooting from three-point range has provided a huge boost. While the Pistons aren’t going to play .700 ball all season, they appear to be a feasible playoff team.

Likelihood of sustaining: 7 out of 10

3. Orlando Magic

With three losses in its past five games — including an ugly one to the lowly Chicago Bulls Saturday — the shine already may be coming off Orlando. This is not surprising considering that Orlando built its early success by burying a ton of three-pointers.

In six victories, the Magic has shot 44.2 percent from three-point range. In four losses, that percentage drops to 34.6. Over the course of 82 games, Orlando likely will wind up somewhere far closer to 34.6 percent than where it is now, which is second in the NBA (trailing only the Golden State Warriors) at an even 40 percent.

But Frank Vogel is a good coach with a strong defensive track record, and the Magic are fifth in the NBA in defense. And after years of tantalizing with his potential, Aaron Gordon looks like a new man playing full-time at power forward, carrying over his success at that spot from the end of last season while putting up the kinds of numbers (19.1 points, 8.9 rebounds and 2.3 assists while shooting over 50 percent from the field) that could place him in all-star contention.

Orlando looks capable of sneaking into one of the final playoff spots in the East, but because of its dependence on the three-point shot this early-season run will be difficult to sustain.

Likelihood of sustaining: 4 out of 10

4. New York Knicks

There were a lot of rumblings about the job security of Knicks Coach Jeff Hornacek after New York lost its first three games. Since then, though, the Knicks have taken off, winning five of six as Kristaps Porzingis blossoms into a franchise player in his third season.

Porzingis has been transcendent, averaging 30.2 points, 7.8 rebounds and 2.2 blocks, while shooting 50 percent from the field and 36.6 percent from three. That Porzingis is putting up those kinds of numbers with the Knicks still completely unsettled at point guard (though rookie Frank Ntilikina had a good performance in Sunday’s win over the Pacers) is a credit both to him and Hornacek, who has done a nice job rallying the troops after the rough start.

Still, it’s hard to see the Knicks sustaining this level of success. Porzingis is good enough that he might be able to drag the Knicks into the playoff race despite the lack of talent around him. But the Knicks still may have the worst point guard rotation in the league, have four centers (including Joakim Noah, who isn’t even back from suspension yet) vying for minutes next to Porzingis and an iffy wing rotation.

That’s why the Knicks are being outscored by their opponents by two points per 100 possessions, and are in the bottom half of the league in both offensive and defensive efficiency. For as fun as the Knicks have been recently, it feels like those numbers will win out in the end, as opposed to New York’s current 5-4 record.

Likelihood of sustaining: 2 out of 10

5. Los Angeles Lakers

With a home win Sunday over the Memphis Grizzlies, the Lonzo Ballers (see what I did there?) are 5-5, including impressive home wins over the Washington Wizards and Detroit Pistons.

But of all of these teams, the Lakers easily feel the most unsustainable. To begin with, they’ve already played seven games at home, winning four of them. For a young team, getting victories on the road is going to be a difficult proposition, particularly in the brutally tough Western Conference.

Beyond that, though, the numbers aren’t in Los Angeles’s favor. The Lakers are 27th in the league in offense, which seems about right. What is hard to comprehend is that they are seventh in defense.

It’s also worth remembering the Lakers started last season 10-10 … and then proceeded to go 11-46 in their next 57 games.

The future looks bright in Los Angeles for plenty of reasons. Ball is a talent, Brandon Ingram has made strides, Kyle Kuzma has impressed as a rookie, and there’s cap space ahead next summer. This early start, though, feels like a mirage.

Likelihood of sustaining: 1 out of 10

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