A tactical guide to the NBA Finals matchup between the Warriors and Celtics

The NBA Finals between the Warriors and Celtics will be a chess match at both ends of the floor. Here’s everything you need to know to prepare.

The differences between the Warriors and Celtics — structurally, stylistically and narratively — are easy to spot, and in many ways, they frame the story of this year’s NBA Finals. This series pits a young, ascendant roster getting over the hump for the first time against an experienced, aging core of veterans returning to a familiar perch atop the NBA landscape.

Golden State has three titles and five (now six) Finals appearances in the last eight seasons, with 123 games of Finals experience between its key players; Boston hasn’t made it out of the East since 2010 and no player on the current roster has ever played in the Finals. The Warriors run an unpredictable and decentralized offense around an off-ball superstar, while the Celtics use a more traditional multi-pronged attack led by two main creators.

In other respects, however, these two sides are quite similar. Both have succeeded by building balanced rosters around homegrown stars, both have proven versatile against different opponents and resilient in the face of adversity, and both have reached this point behind the strength of their defenses. Boston and Golden State ranked first and second, respectively, in defensive efficiency this season, and have been two of the league’s most innovative and adaptive defenses throughout the year. That, as much as anything else, will define how this year’s NBA Finals play out, and this series will present both teams with new problems to solve.

How will the Boston Celtics defend the Golden State Warriors in the NBA Finals?

Boston’s multifaceted offense stands in stark contrast to the heliocentric one the Warriors faced in the Conference Finals, and the Warriors present a completely different — and more difficult — challenge than the teams the Celtics took out en route to the Finals. Golden State’s 117.8 playoff offensive rating leads the NBA, and Boston has not yet faced a team that can score in as many ways as the Warriors can.

The Warriors incorporate many of the same read-and-react principles the Heat did, only with greater precision and decisiveness. They force opponents to cover more ground, make quicker decisions, consider more options and stay more connected than perhaps any other team in the league, and have arguably the most lethal offensive weapon in the game right now.

If there’s a model for how to beat the Warriors, it’s the Memphis Grizzlies’ combination of balanced offense and all-out defensive pressure, which flustered Golden State into by far its worst series of the postseason. The Celtics have the personnel to replicate that approach, but with better offensive creators and more versatile and disciplined defenders. There may not be a team in the NBA better equipped than Boston to deal with the Warriors’ constant flow of cuts, screens and passes.

That task starts, as ever, with containing Steph Curry, whose perpetual motion and scheme-bending gravity are too strong for any one defender — or even conventional coverages — to contain. It might be easier, in theory, for a team to dry up Curry’s individual production than Kevin Durant, Giannis Antetokounmpo or Jimmy Butler’s, but Curry is a superior offensive creator because of the of attention he draws beyond the 3-point line and how he exploits that attention with his off-ball movement:

The matchups in this series will be fluid because of how often the Warriors move and screen, but to the extent that conventional defensive assignments do exist, Marcus Smart seems like the most logical candidate to guard Curry because of his size and screen navigation on and off the ball. Don’t be surprised, however, if Ime Udoka experiments with Smart on Draymond Green while Jaylen Brown or Derrick White chases Curry. Boston seemed unwilling to switch Robert Williams and Al Hoford, their best rim protectors, onto Curry in the regular season, which the Warriors exploited by using their men (often Green and Kevon Looney) as a screener for Curry:

Putting a smaller defender on Green would not only free Williams and Horford to make plays in help defense, but allow Boston to switch Curry-Green pick-and-rolls more smoothly. That two-man game triggers an automatic trap for most opponents, which allows Green — possibly the best off-the-dribble passing big man ever — to make plays against a compromised defense. Switching that action would allow the Celtics to more easily keep the play in front of them and avoid costly four-on-three scenarios.

The same is true off the ball, where Golden State generates most of its offense from improvised cuts and screens designed to create confusion and force defensive lapses. But if defenses can simply switch those off-ball actions with like-sized defenders, as the Celtics can, it becomes much easier to seal those openings and force tougher shots:

Udoka will deploy different schemes throughout the series to keep Golden State on its toes — one of the many benefits of coaching a team with Boston’s level of athleticism, intelligence and discipline. The Celtics are almost perfectly designed to switch everything, yet their guards’ ability to fight over ball screens makes drop coverage viable in lineups with two bigs on the floor, and Boston’s ability to scramble around the floor could also make trapping Curry survivable.

Right now, switching looks like their best option, if only because it mitigates the Warriors’ ability to create easy looks off of Curry’s gravity. If that’s the case, Klay Thompson and Andrew Wiggins might find their looks harder to come by in this series, so Curry and Jordan Poole must be able to reliably beat their defenders one-on-one for Golden State to score consistently. If they aren’t switching, the Celtics may try helping off of Green and Looney to shut off driving and passing lanes, but those two are experts at pivoting into handoffs with shooters when opponents ignore them.

How will the Warriors defend the Celtics?

Injuries to Andre Iguodala, Gary Payton II and Otto Porter Jr. somewhat compromise the Warriors’ depth and ball movement, but the greater cost of their unavailability would come on defense. Despite his advanced age, Iguodala remains a savvy individual and team defender, Porter is a dogged rebounder and off-ball defender in small lineups, and Payton is arguably the best defensive guard in basketball. As of this writing, none of the three have been ruled in or out for Game 1.

Regardless of Porter, Payton and Iguodala’s status, Wiggins will almost certainly start the series defending Tatum, with other Warriors also taking turns on him throughout the series. Tatum’s passing has reached a new level this postseason, and he’ll need to fully unlock that part of his game to overcome a smothering, disciplined defense. The Warriors won’t swipe at the ball or jump passing lanes as aggressively as the Heat did, but they masterfully shrink the court on their opponents while providing fewer weak links to attack. They’re the rare team that can swarm the paint and still recover to shooters and will dare Smart, White, Grant Williams and even Horford to beat them from 3.

The Warriors were comfortable switching their guards onto Tatum in the regular season, and have plenty of past experience protecting smaller players from superstars by hedging and pre-switching against the pick-and-roll. But the Celtics haven’t hunted mismatches as aggressively as some other teams in the playoffs, nor is it in their best interest to do so.

Tatum can get a shot off in most any situation but has scored just 67 points on 80 isolation possessions this postseason, with a high turnover rate and minuscule free-throw rate. As a team, the Celtics rank in just the 40th percentile among playoff teams in isolation efficiency and are at their best when they move the ball and get into the teeth of the defense. They should and will pick on Poole when he’s in the game, and Brown should be able to pick his spots in isolation, but if Boston falls back on playing one-on-one in the halfcourt this may be a short series.

Brown and Tatum will see bodies on every foray to the basket and need to consistently recognize when to pass in those situations. Sometimes the right pass is also the simplest one, and those two have gotten better at getting off the ball early against traps and hedges on the perimeter, which allows Boston to move the ball against a rotating defense. The Celtics have used Smart and White as screeners for Tatum a ton in the playoffs, which either forces opponents to switch a smaller defender onto Tatum or lets Boston’s guards make plays on the roll:

That action also gives Boston a way to make Curry work on defense without reducing its offense to a one-on-one game, and the Celtics will involve Poole in that action as well. The Warriors can also be vulnerable on the perimeter against the ultra-quick ball-handlers, though Boston doesn’t have a ton of speed off the dribble. Curry and Looney might appear easy targets, but the former is a stout, competitive defender while Looney has become one of the best switching big men in the NBA. (If the Celtics are going to attack anyone, it should be Poole or Thompson.)

Expect Boston to run quick-hitting plays designed to get Brown attacking downhill, where he can use his physical advantages to either finish at the rim or rise up over his defender. His quick first step and Thompson’s diminished mobility might lead Steve Kerr to eventually shift Wiggins onto Brown and Thompson on Tatum, where Thompson can use his size without as much risk of getting blown by.

Golden State is liable to change its defensive scheme from possession to possession, and the Celtics must come out of the gate ready to attack not only different man-to-man coverages but various iterations of zone defense as well. Kerr will also play a deeper rotation than Udoka, especially if Golden State gets fully healthy, and which team’s bench holds the fort in star-less minutes will be critical.

Relatedly, the amount of rope Kerr gives lineups without Curry or Green will be worth watching; Poole’s emergence and Thompson’s return to form have allowed Golden State to line up more of Steph and Draymond’s minutes in the playoffs, but bench-heavy units have predictably been inconsistent, especially on defense.

What factors will swing the NBA Finals?

Pay attention to when each coach decides to go small from game to game. Both teams have dynamic small-ball lineups at their disposal, but the centers in this series have been so good throughout the playoffs that Kerr and Udoka might stay big for longer than expected. If Looney or Robert Williams gets pulled off the floor in crunch time, it will be more about their offense than their defense.

Looney and Wiggins punished the Grizzlies and Mavericks for going small by attacking the offensive glass, and the Celtics must find bodies when shots are in the air and punctuate stops with defensive boards.

This series may ultimately swing on turnovers and transition defense. In a battle between elite halfcourt defenses, cleaning up miscues and limiting the opponent’s opportunities for easy points will be paramount. Golden State and Boston have the seventh- and eighth-highest turnover rates among playoff teams and their transition defenses have suffered as a result. The Celtics have allowed the most transition points per 100 possessions of any team that made it past the first round, while the Warriors are prone to spells of careless passes that lead to runouts on the other end. Boston can’t afford to linger behind the play and complain to the refs like it did against Miami (Tatum has been a particularly bad offender here) and feed Golden State’s fast-paced, 3-point hungry offense.

The Celtics are younger than most NBA Finalists, but this postseason, which includes elimination-game wins in Milwaukee and Miami, has left no doubt about their toughness and resolve. Golden State, meanwhile, has carved its way through the West with the steel and confidence of a team that lives for the playoff crucible. This series will be defined by elite defense, which means it will favor the team with the more resilient offense. As good as Boston is defensively, the Warriors may be just as good on that end and have more ways to attack on offense. That, the disparity in Finals experience and the fact that the Warriors have the best player in the series all sway me toward picking Golden State in six, though the series could just as easily go the other way.

Beyond the obvious catharsis of winning a title, the stakes of this series are significant — particularly for Golden State, who may not get a better shot at a post-Durant title with this core of players. A fourth ring would put Curry beyond reproach as one of the game’s all-time greats, elevate Green as one of the greatest complementary players ever, cap off Thompson’s arduous road back from injury and stamp these Warriors as one of the game’s most enduring player-coach marriages.

For Boston, a win would vindicate a circuitous and oft-questioned team-building process around Tatum and Brown, reward Horford for a career of winning basketball and give Tatum something no other under-25 superstar has. All of that and more will be decided in the coming weeks. Lucky for us that we get to watch it unfold.