Once upon a time, there were five positions on a basketball court at a time: point guard, shooting guard, small forward, power forward and center. Now, the game has evolved to a point of positional fluidity where individual players don’t align perfectly with their archetypal predecessors.

The emphasis on shooting at the 4, switching and the rise of players built like wings who control the offense has made the NBA world reconsider what these designations mean—and whether it’s necessary to be pigeonholed into a positional denomination. The All-Star game transitioned from naming positions on the team to identifying only backcourt and frontcourt players. Some believe the center position is an outdated category for All-NBA selections.

Brad Stevens, head coach of the Boston Celtics, has even stated he doesn’t guide his team within the confines of positions.

“I don’t have the five positions anymore,” he said, per Kareem Copeland of the Associated Press. “It may be as simple as three positions now, where you’re either a ball-handler, a wing or a big.”

Don’t tell me about positionless basketball. I don’t want to hear it.

I don’t disagree with Brad Stevens, per se. I understand. But classifying ball-handler, wing and big as positions is…blasphemous. Stevens and others are crafting lineups with players in mind that can perform certain roles. They aren’t abandoning positions, nor are they limiting the number of them to three. But stereotyping a player and how they function within a team based on their size and shape has gone by the wayside.

A lineup needs a certain number of roles filled to conquer its primary aim: scoring more points than the opponent can muster. For example, a primary ball-handler is needed to initiate the offense. This can be done with an archetypal point guard like Chris Paul, or an elite ball-handling big like LeBron James. The Celtics had Isaiah Thomas fit that role last season. However, they met adversity against certain teams because they did not have a player who could reliably operate as a secondary ball-handler when Thomas failed to escape a defensive stalwart or double-team. They adjusted in the offseason, grabbing Gordon Hayward to play second fiddle.

Marcus Smart, Terry Rozier and Avery Bradley sometimes functioned as the auxiliary ball-handler, but Thomas’ size deficiency and inability to defend opposing 2-guards put Smart and Rozier in constant mismatches against larger wings. Stevens bet the Celtics would be more successful with a defensive mismatch at the 2 over lineups that didn’t give Thomas a capable teammate to initiate. Bradley and Smart actually performed admirably in those secondary ball-handling roles, but both are under 6’4″ and should not play together with Thomas. Size still matters on the perimeter. NBA coaches are futzing with puzzle pieces in their lineups as much as their play designs are chess.

A team in today’s NBA isn’t focused on filling positions. It’s trying to create lineups that satisfy job descriptions best suited to match up with their opponent.

Building the Ideal Offense

Offensive Roles:

• Primary Ball-Handler
• Secondary Ball-Handler
• Timely Cutter
• Three-Point Threat
• Post-Up Player
• Effective Screener
• Rim-Runner
• Pick-and-Pop Shooter
• Offensive rebounder
• Isolation Threat
• Knockdown Mid-Range Shooter

Teams need the right mix and balance of these skill sets on the court at all times. The Celtics offense would stall last season because it didn’t have a secondary ball-handler, second isolation threat or post-up player to bail out Thomas when he couldn’t manufacture points. The Chicago Bulls didn’t have enough three-point shooters to create the space necessary for their primary and secondary playmakers (Dwyane Wade, Rajon Rondo, Jimmy Butler) to score efficiently. Opposing defenses were able to collapse on the paint when they controlled the ball because the Bulls didn’t have a good lineup composition. These are perfect examples of why squads must collect diverse, effective players—so that, when the time comes, they can adjust and play different styles.

Although I’ve mentioned the Celtics twice for their lack of secondary ball-handling options, they actually did a tremendous job finding versatile players before the 2016–17 season.

If they needed an additional wing defender on the court, they had a bevy of options in Bradley, Jae Crowder, Jaylen Brown and Gerald Green who could give them lineup flexibility. Crowder and, to a lesser extent, Brown and Green have the size to adequately defend 4s or larger wings. When Boston met the Cleveland Cavaliers in the playoffs, it struggled to score with Crowder as the third wing defender at the 4. So it adjusted, dusting off Jonas Jerebko to act as a pick-and-pop shooter, three-point threat and stronger defensive rebounder. Boston continued to emphasize this versatility and lineup flexibility over the offseason. It acquired Marcus Morris as an upgrade over Jerebko, Jayson Tatum as an isolation threat and Hayward as a secondary ball-handler who, like Morris, can fill the role of wing defender on defense.

So how do these puzzle pieces fit together to create a good team makeup?

On offense, it is critical to have both a primary and secondary handler. LeBron James needs his Kyrie Irving, even if it’s not actually Kyrie Irving. Damian Lilliard needs his C.J. McCollum. But the No. 2 doesn’t necessarily need to be someone who can break down an opponent off the dribble in isolation. Stephen Curry has long had Draymond Green as his second banana, and he’s no one-on-one specialist. It may be more accurate to call him a passer or creator instead of a ball-handler, which is why the term point-forward has caught on to define larger offense initiators.

Players who can fill multiple offensive roles on a given possession are more valuable than those who are one-dimensional. Elfrid Payton, for example, has hit his offensive ceiling because he’s not a three-point threat or viable off-ball option. On any given possession, Curry can pass to Green and then operate as a catch-and-shoot three-point threat. Curry is an excellent cutter and, when all else fails, a fantastic isolation scorer. He offers absurd value in multiple roles, whereas someone like Monta Ellis is limited in how he can contribute. His narrow skill set forces a coach to build an offense around his basketball abilities.

Obsessions with the three continue to permeate the league—and rightfully so, since good spacing changes everything. But a player can be effective even if he is not a three-point threat.

DeMar DeRozan—a solid cutter, ball-handler, isolation scorer and mid-range shooter–is a star. His inability to hit threes narrows offensive possibilities for the Toronto Raptors, and he doesn’t create as much space as a shooter like C.J. Miles when playing off the ball, but he’s still a positive contributor (on one end) because he masters other machinations that offset his shooting deficiencies:

Bigs fill roles, too.

Shorter guards are limited on offense just as they are on defense. Most smaller players are not effective post scorers, rim-runners or screeners. Big men, however, can fill almost any role if they are mobile and skilled enough. Clint Capela has carved out a niche as a screener and rim-runner for the Houston Rockets. DeAndre Jordan has made a career of doing the same, though he is activated by fantastic ball-handlers and passers:

Other skilled skyscrapers like Channing Frye and Ryan Anderson have found their calling card off the pick-and-pop or on the wing:

Certain towers are revolutionizing the sport by mixing every sort of role into one. Giannis Antetokoumpo is the ultimate Unicorn—a primary ball-handler, rim-runner, devastating cutter and isolation scorer who stands nearly 7’0″.

Some guards like Russell Westbrook and Bradley distinguish themselves further with tenacious offensive rebounding. This is yet another example of a player establishing himself as a threat within an area that runs counter to his size, similar to bigs who shoot and handle the ball. The significant difference: Offensive rebounds aren’t seen as high-value offerings. Although they revive a possession, sending a player to the offensive glass removes him from the transition-defense setup and places his team at a potential disadvantage. Henry Abbott noted the dubious benefit of offensive rebounds in the context of the late-aughts Boston Celtics, who posted the worst-ever offensive rebounding percentage.

Now, let’s recap with more nuance. Capable offenses need the following:

• A primary ball-handler to run the offense.
• A secondary ball-handler or post-up player to provide another offensive option should the primary ball-handler be stifled.
• A rim-Runner, pick-and-pop big or screener to let ball-handlers attack mismatches. Screeners can be effective in off-ball situations.
• Two three-point Shooters to create space.
• One, but preferably two, isolation Scorers, mid-range shooters or cutters to manufacture even more space for ball-handlers or take advantage of the generated space.
• Offensive rebounders and mid-range shooters are useful, but not absolutely necessary for successful offensive lineup composition.

This criteria is not completely rigid. Superstar players tend to create instances where they can cover for the absence of a role or two.

The Houston Rockets often run lineups in which James Harden is the only ball-handler surrounded by three-point threats and a rim-runner. But even they acknowledged the need to acquire more playmaking to ease the burden on Harden. They acquired Lou Williams before last year’s trade deadline and then added Chris Paul over the offseason to provide another distribution hub for playoff games that require lineup flexibility and reactability.

Overall, though, quality offensive lineups need players who can fill all or most of these roles.

Building the Ideal Defense

Defensive Roles:

• Rim-Protector
• Wing Defender
• Defensive Rebounder
• Defensive Floor General
• A Big Comfortable Defending on Perimeter

Crafting a capable defense is, quite simply, predicated on finding good stoppers. Here’s the problem: Half of the NBA isn’t good at defending. Whether it’s the elite offensive play or the NBA’s hand-checking rules, it is incredibly difficult for players to ward off elite athletes.

A good rim-protector is probably the most important defensive asset. Layups and dunks remain the NBA’s highest-quality looks. An elite rim-protector’s objective is shot contention and deterrence. They must be able to lower the quality of an opponent’s shot attempt, but they also dissuade rival players from even attempting such an offering. These guardians of the paint push the average distance of shots out away from the basket, increasing the level of offensive difficulty for their foes. A weakside rim-protector covers the mistakes of his teammates.

That’s why players like Rudy Gobert are perpetual Defensive Player of the Year candidates:

Rim-protectors must be deterrents more so than shot-swatters. Hassan Whiteside was lauded for his impressive block numbers before Miami Heat head coach Erik Spoelstra and NBA Twitter turned on him, realizing he chased such opportunities at the expense of his team. Bill Russell and Tim Duncan were preeminent rim-protectors—not because of their block highlights, but because of their cerebral anticipation and understanding that deterrence is more important than anything.

As we have talked about numerous times, the league is in the throes of a switching frenzy in response to the spread pick-and-roll actions run by every team. For a refresher on this type of defense, no one switches like the Spurs.

A defense needs multiple wing defenders to stay home on three-point shooters and navigate switches. Teams understand most point guards are their rival’s weakest defenders; as the slightest players on the floor, they’re at an inherent physical disadvantage. Coaches will often put their best wing defender on the opposing floor general. It’s a game of strengths: Put your strongest individual defender on the opposing team’s most effective ball-handler.

Golden State does this often. Curry guards lesser wing players so the long and staunch Klay Thompson can smother ball-handlers.

You may notice there isn’t a role in the defensive subset distinctly for slighter players. That’s not by accident. A team does not need to have the shortest player on the floor to be a solid defensive team. They may actually be better without one. The Milwaukee Bucks and others have tinkered with this idea: the abolition of a shorter guard for the sake of allowing another lanky wing defender to take the floor. In many Bucks lineups, Malcolm Brogdon (at 6’5″ with a 6’10 “wingspan) will be the shortest player on the court. The two most frequent lineups involving Brogdon played him at point guard next to long behemoths like Khris Middleton and Antetokounmpo.

Most of the time, when a lineup does not have a tall ball-handler, opposing teams are forced to reckon with a typical 1-4 or 1-5 pick-and-roll that draws one of their rim protectors to the outside. Bigs with the athleticism to stick with guards and rotate laterally have become increasingly valuable for this exact reason. And that, in turn, has helped spur the Unicorn Movement, with Serge Ibaka putting in shifts as the switched defender for the early-2010s Oklahoma City Thunder and on his current team, the Toronto Raptors.

Teams can try performing without elite defensive rebounders if they compensate by funneling their wing defenders toward the glass instead of having them get back in transition. The Celtics, playing Al Horford as their nominal center, tried this during the 2016-17 season and enjoyed reasonable results. But they also frequently gave up offensive rebounds, allowing opponents to revive their possessions. The Celtics ranked No. 29 in defensive rebounding percentage, largely as a direct result of their diminutive frontcourt. Second-chance opportunities put stress on a defense, so it’s always nice to have high-level rebounders on the less glamorous end. Long, physical freaks like DeAndre Jordan and Whiteside hound the glass and save possessions from untimely offensive boards.

The final role, the defensive floor general, is tricky.

Finding candidates to fill this job description isn’t a matter of poring over measurable skill sets. A player who is able to read the defense and call out opposing sets is incredibly valuable. Not everyone on the court will be an excellent defender, so cohesion and communication largely hinges on one leader helping coordinate his teammates. Rajon Rondo assumed this role during the first part of the Bulls’ 2016 playoff series with the Celtics. Dwyane Wade, Rondo’s teammate in Chicago, once remarked on how he hated playing against the pesky point guard because he would call out all of their plays. Rondo’s knowledge of other team would change the game’s dynamic.

Draymond Green and Tim Duncan are famous for their vocal leadership and understanding of a rival’s offense, as well. We don’t have a statistic to measure that.

So, to recap once more, the most capable defenses need the following attributes from their five players on the court:

• One rim-protector
• A combination of two to three wing defenders and bigs comfortable defending on perimeter
• One strong defensive rebounder
• One defensive floor general

The degree to which defenders can play multiple roles is limited. Players guard the individual opponent in front of them while functioning within team-oriented schemes. Their puzzle-piece movement is predicated on a collective ability to read the opposing team and prevent mismatches rather than fill roles. That makes defense difficult, especially when individual liabilities are on the floor. The Cleveland Cavaliers were the best team in the Eastern Conference this past season, but Kevin Love and Kyrie Irving were routinely hunted down as the weakest links. It’s hard to find good defenders who double as excellent offensive players.

Players deficient on one end of the court change the dynamic and objective of the lineup in the game. Irving’s defensive shortcomings and Tony Allen’s inability to space the floor warp their squad for the worse. These one-sided talents have a place in the league, but they complicate the task at hand when in the game. Allen’s team must score under greater pressure with him in the fold, while Irving’s running mates constantly have to keep an eye out for the next defensive collapse from his side of the floor. Players must be two-way contributors to have the best possible impact. They can’t excel on offense or defense. They have to play both.

Some players can play multiple defensive roles, but they’re few and far between. Shorter rim-protectors who dabble as competent defenders on the perimeter are incredibly valuable—hence why Draymond Green, Kevin Durant and Giannis Antetokounmpo shine. Unicorns have become so special because they boast a similarly high ceiling for both rim and perimeter protection. Their height, length and abnormal lateral quickness sets them apart.

Creating lineups that have the flexibility to continually field an elite offense and defense is extremely difficulty. Teams have just 15 roster spots, only eight to nine of which warrant rotation time in the playoffs. But front offices and coaching staffs must figure how to acquire and develop players who fill all of the roles necessary to score and defend. Some combinations will pile on points while playing poor defense—and vice versa. Teams are responsible for identifying those lineups during the regular season, all with the playoffs in mind.

Mediocre players who rely on skills that don’t align with the pacing and intensity of the postseason become less effective…and sometimes unplayable. The San Antonio Spurs are the premier franchise when it comes to applying a player’s skill set with team fit. Coaching and systemic dominance play a part in this, but more than anything, head honcho Gregg Popovich and general manager R.C. Buford have built their dynasty by creating versatile rosters and placing players in roles that allow them to succeed. The Spurs use the regular season not to rack up stats for their All-Stars, but to hone their rotations. They seek to make their players comfortable and confident, and it shows when they exceed expectations in the playoffs. That’s why the Spurs have survived for two decades as a top franchise.

They have cracked the code on how to ideally manage and develop players within their roles.

Follow Ryan on Twitter @jarvrt14.

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Unless otherwise indicated, all stats are from NBA Math, Basketball Reference or NBA.com.