For years, the San Antonio Spurs have been among the NBA's steadiest presences. And sure, it helps to have Tim Duncan, Manu Ginobili and Tony Parker for well over a decade. But deep benches have been a hallmark of that organization's success.

Conversely, teams that fall apart when their top guys leave the floor have had a hard time finding sustained success. The focus here is on those squads.

To predict which teams might have the worst benches, we'll look at the average preseason rankings for every player in the league from outlets like Sports Illustrated, CBS Sports, ESPN, FiveThirtyEight and NBA Math.

If we sort every roster by the average of their ranks from those outlets, then combine the averages for Players 6 through 10, we can get a rough estimate on the depth of all 30 teams.

This certainly shouldn't be taken as definitive, but a "wisdom of the crowd" approach yields results that feel pretty accurate.

The Top 20

We won't spend a ton of time here since the article is about the worst benches. But it's worth mentioning how the rest of the league shook out in this exercise:

1. Denver Nuggets
2. Sacramento Kings
3. Orlando Magic
4. San Antonio Spurs
5. Los Angeles Clippers
6. Brooklyn Nets
7. New Orleans Pelicans
8. Dallas Mavericks
9. Phoenix Suns
10. Memphis Grizzlies
11. Utah Jazz
12. Chicago Bulls
13. Milwaukee Bucks
14. Los Angeles Lakers
15. New York Knicks
16. Houston Rockets
17. Minnesota Timberwolves
18. Indiana Pacers
19. Miami Heat
20. Oklahoma City Thunder

There are certainly some surprises in the top 20. But for some of the teams that appear destined for the lottery, there may not be much of a gap between the bench and the starters.

What isn't surprising, though, is that the Nuggets are first. This team is loaded. Beyond the well-balanced starting five led by Nikola Jokic, Denver boasts Monte Morris, Malik Beasley, Michael Porter Jr., Jerami Grant, Mason Plumlee and Juan Hernangomez as potential bench players.

There's a decent chance the Nuggets have the deepest roster in the NBA.

25-21: Pistons, 76ers, Celtics, Raptors, Warriors

This group features five potential playoff teams (and four near-locks) whose benches may be causes for real concern.

21. Detroit Pistons

There's plenty of talent between Blake Griffin and Andre Drummond, but Detroit's roster is largely question marks after that. And that, of course, includes the bench.

Derrick Rose is an interesting addition as a potential heat-check guy off the pine, but he finished 2018-19 at a woeful 3.3 percent from deep over his final 17 appearances. He hasn't had an above-average box plus/minus campaign since 2011-12.

Markieff Morris, Luke Kennard (if he doesn't start) or even Joe Johnson might provide a little hope for the second unit as well. But no one feels like anything close to a sure thing.

22. Philadelphia 76ers

Philadelphia's starting five has the potential to be the best in the NBA. But after Ben Simmons, Josh Richardson, Tobias Harris, Al Horford and Joel Embiid, things get dicey in a hurry.

If one of Trey Burke or Mike Scott pops, this outlook might be different. Both Matisse Thybulle and Zhaire Smith have plenty of potential. Staggering the starting bigs could allow Horford or Embiid to lead bench units.

Like Detroit, though, those potentialities are little more than that right now. The starters may have to post some massive plus-minus numbers.

23. Boston Celtics

The Celtics recovered nicely from the loss of Kyrie Irving by adding Kemba Walker in the (pre-)opening moments of free agency. But like Philadelphia, this team features a bench that could make things difficult on the starters.

Marcus Smart is a true basketball Swiss Army knife. But after that, Boston is relying on a lot of youngsters off the bench. Is Grant Williams ready for that kind of responsibility? Carsen Edwards?

Proper staggering, or perhaps reserving Enes Kanter for a sixth-man role, could mitigate this to an extent. But Celtics fans should feel a little uneasy about the second unit.

24. Toronto Raptors

It's tough to fault the Raptors for this position. There isn't much they could've done differently to hang onto superstar Kawhi Leonard. They won the title, for crying out loud.

But leave he did. And that pretty much sealed Danny Green's departure, too. Toronto was minus-2.5 points per 100 possessions (39th percentile) when it played without both those starting wings last season, according to Cleaning the Glass.

Norman Powell and OG Anunoby will be tasked with replacing them (good luck when Kawhi is 11th all-time in career box plus/minus, while Green is 82nd), which leaves even lesser names to fill their roles off the pine.

25. Golden State Warriors

Only so much can be learned from a preseason game, but Golden State's debut against the Lakers put a major weakness on display. Warriors not named Stephen Curry shot 38.5 percent from the field and generally had a hard time creating any offense independent of their superstar.

Things will certainly loosen up a bit once Klay Thompson returns, but expecting consistency from young players such as Alfonzo McKinnie, Jordan Poole and Jacob Evans could make it tough for Golden State to hang on until that happens.

26. Portland Trail Blazers

The Portland Trail Blazers are almost like the bizarro Pistons.

Detroit's roster sort of falls apart after the two bigs up top. For Portland, it's after the two guards: Damian Lillard and CJ McCollum.

Those two have certainly carried their fair share of responsibility over the years. They carried it all the way to the Western Conference Finals last season. But in 2019-20, the burden may finally be too much.

Last season's No. 3 player in Rip City (No. 2 by most advanced metrics) will likely miss much of the season.

"[Portland general manager Neil] Olshey says the Blazers plan on being 'purposefully vague' regarding Jusuf Nurkic's rehab," The Oregonian's Joe Freeman tweeted. "Said he doesn't want a 'Nurkic Watch.' But ... he is in town, working out and shooting, and progressing toward his next 'benchmark.'"

Over the nearly 1,000 possessions Lillard and McCollum played without Nurkic last season, Portland was minus-5.1 points per 100 possessions (28th percentile). And while Hassan Whiteside is there to bridge the gap between now and Nurk's eventual return, he wasn't quite on the same level last season.

Nurkic's superior playmaking allowed Lillard and McCollum to spend a few more possessions off the ball, adding some variety to the offense. His positional defense helped, too.

Whiteside can replicate some of the defense. Passing has never been his strong suit.

After that, the roster is loaded with question marks. Consistency has always been an issue for Rodney Hood. Zach Collins, Nassir Little and Anfernee Simons are largely untested. Mario Hezonja may be on his last chance. Kent Bazemore has been below-average in both box plus/minus and true shooting percentage over the last three years.

Two or three of those players working out wouldn't be shocking, but neither would the opposite.

"And Olshey said 'don't expect fireworks.'" The Athletic's Jason Quick tweeted in the wake of Portland's free-agency overhaul. "What a stunning display of elevating Blazers to another tier. Whiteside, Hood, Bazemore, Hezonja, Little. Pretty impressive."

In response, former Blazer Evan Turner tweeted that last year's crew would "run them out of the gym." And he may not be wrong.

The players Quick referenced are projected by FiveThirtyEight for 1.8 wins above replacement this season. The players Turner brought up are projected for 4.1.

27. Atlanta Hawks

The Atlanta Hawks are one of the most exciting young teams in the NBA.

Last season, then-rookie Trae Young averaged 24.7 points, 9.2 assists and 2.4 threes with a 57.6 true shooting percentage after the All-Star break. Shaquille O'Neal, Blake Griffin and Karl-Anthony Towns are the only players in league history to match John Collins' per-possession averages in an age-21 (or younger) season. Kevin Huerter shot 38.5 percent from three and showed some playmaking chops from the wing.

Those three make up a long-term core that could have the Hawks in playoff contention within the next few years. The rest of the roster, however, leaves plenty to be desired.

Atlanta has a trio of veterans in Jabari Parker, Allen Crabbe and Evan Turner. Among those three, Turner had the best box plus/minus, and he finished 208th out of 276 players with at least 1,000 minutes last season.

Alex Len, De'Andre Hunter, Cam Reddish, DeAndre' Bembry and Damian Jones all offer varying levels of intrigue, but not a whole lot more at this point. Vince Carter is 42 years old.

Of course, a couple of those players will start alongside the burgeoning Big Three. But whatever combination is left on the bench could be in for some tough minutes.

28. Charlotte Hornets

The Charlotte Hornets have a decent chance to be the NBA's worst team in 2019-20.

Over the last three seasons, they were plus-2.5 points per 100 possessions when Kemba Walker was on the floor and minus-6.6 when he was off. And now, of course, Kemba is gone. Terry Rozier is in his place.

Among the 438 players who've hoisted as many career three-point attempts, Rozier's effective field-goal percentage ranks 393rd.

Having him lead a starting five that could include Nicolas Batum, Dwayne Bacon, Miles Bridges and Cody Zeller screams problems. And naturally, the bench is worse.

HoopsHype's Frank Urbina summarized the roster:

"The roster is extremely weak … They don't boast a single player at the Top 15 of their respective positions … The majority of the roster is either completely unproven or declining, as is the case with Batum and Williams … Their past draft misses and poor decisions in free agency have really caught up to them … Very low flexibility to acquire future assets in trades like most lottery-bound teams do during the season … The depth at the point is anything but reliable … No player in the roster averaged more than 10.1 points in the NBA last season."

For Hornets fans, perhaps there's some hope that Bridges or Malik Monk could take off. Maybe PJ Washington can offer some excitement as a rookie. One or both of the Martin twins (Cody and Caleb) working out would be cool.

But in the short term, this team could be brutal.

29. Cleveland Cavaliers

Like Atlanta, the Cleveland Cavaliers have a young core you could see in a playoff series a few years down the road. You might just have to squint a little harder.

Despite historically bad advanced numbers (2,841st out of 2,842 rookie seasons in value over replacement player, ahead of only Kevin Knox), Collin Sexton's 16.7 points per game and 40.2 three-point percentage offer some hope. Dual-point guard lineups with him and incoming rookie Darius Garland could be fun.

Cedi Osman has some point-forward potential. Advanced numbers love Larry Nance Jr. Oh, and Kevin Love is still around...for now.

But when this team goes with bench-heavy lineups, plenty of games are going to get blown wide-open.

Brandon Knight, Jordan Clarkson, Ante Zizic and Matthew Dellavedova were all replacement-level (minus-2.0) or worse in box plus/minus last season. Dellavedova was way worse. The only two players who were above-average were Nance (plus-4.0) and Tristan Thompson (plus-0.3).

Without someone drastically outperforming expectations, cobbling together positive second-unit minutes is going to be nearly impossible for this squad.

Instead, fans could be treated to loads of contested jumpers from Clarkson and Knight. They'll just have to remind themselves this season can't last forever and at least one of the youngsters hitting feels likely.

30. Washington Wizards

While the Pistons and Blazers have just two players before things get dicey, the Washington Wizards may only have one. With John Wall recovering from a ruptured Achilles, Bradley Beal is about as close to a one-man show as you'll find in the NBA during the 2019-20 campaign.

The list of players who could log minutes off the bench for this team could require an awful lot of Wikipedia searches for the average fan:

• Ian Mahinmi
• CJ Miles
• Thomas Bryant
• Davis Bertans
• Ish Smith
• Rui Hachimura
• Troy Brown Jr.
• Moritz Wagner
• Jordan McRae
• Isaiah Thomas
• Isaac Bonga
• Justin Anderson
• Jemerrio Jones
• Admiral Schofield

Pick four from that lot to start and then imagine what the second unit looks like. And this doesn't even touch on the non-guaranteed contracts and two-way guys who'll likely find some time on a team as bad as this.

If Hachimura doesn't give fans something to dream about for the future, this could be a tough season to stomach.

All stats, unless otherwise indicated, courtesy of Basketball Reference, NBA.com and Cleaning the Glass.