The Celtics’ defense was once a monolith.
It was supposed to be this big black box, a neural network of switches that operated automatically from its base inputs. But as the playoffs drag on, this unit whose accolades range from best in the league at minimum to best one generation to one, well, median if we’re being honest, has become more diverse and predictably unpredictable. Ime Udoka and his team built the hidden layer to give this defense more variance and complexity than all season.
The Celtics made the NBA Finals not because they could stop everything from happening by changing every game, but because they were able to invite the opponent into what was supposed to be a comfort zone. , then turn up the heat just when the attack thought. it became comfortable.
The idea of defensive homogeneity is so talked about that the Celtics switch defense is so big because everyone is close enough in size that their versatility is seemingly endless. But that’s what made them great in the regular season. In the playoffs, personnel can be mitigated by scheme and execution. Everyone has a weakness, even Defensive Player of the Year, and it can be targeted. But that still hasn’t happened in Boston because his versatility isn’t just in the consistency of his heights and wingspans.
Boston has built one of the great switch defenses of the modern era, particularly because it’s similar in size across the board, but doesn’t always need to change. The Celtics struggled at the start of the year to change everything, eventually found themselves on the same page calling actions and cleaning up mistakes, then added layers of drop covers to accommodate personnel at the microphone level. The Heat tested this better than anyone, as Boston was forced to play a deep drop for most of the series knowing when to switch based on screen location and offensive personnel combinations.
The Warriors force you to do these readings constantly throughout the night at odd angles and at full speed. The only time the ball really slows is when Draymond Green is waiting for a cutter to take a dribble handoff (DHO), but he’s a major threat to fake those handoffs and roll in the paint where he’ll find a shooter open . So Boston needs to be extremely disciplined on both counts, sitting under the stocks while still being able to get up against the shooters when Steph Curry or Klay Thompson grabs the ball and launches into a one-motion shot.
So how will Udoka incorporate his zoning principles into a series against a team that turns a glimpse of gold into a gold mine?
In previous games, Rob Williams spent a lot of time sitting under the stocks as the Celtics chased down the screens, so the Warriors dragged their screens to the corners so Boston had to stay between the offensive player and the basket. It would give players like Thompson the chance to get up from the corner and make a clean grab while Jaylen Brown would be caught under a screen and Williams would be behind him.
The funny thing about covering the Warriors is that the dripping cover doesn’t really look like a dripping cover. In the series with Miami and Milwaukee, Boston was down as a big thundered in the lane past a downhill rider looking to get a small defender on his hip to drive deep into the paint. The Warriors don’t do a ton of that. There’s not a lot of high pick-and-roll. There’s not much of a regular ballhandler taking it on the screen with the big one then diving towards the edge. The direction everything is going is unpredictable and works almost the opposite of most NBA teams.
That’s why Udoka drops Williams under this action below, as he can basically zone any of the 45 cuts the Warriors like to make where they head straight for the hoop from the wing. But that makes them vulnerable to games like this.
It missed. But who cares. It’s a wide open Curry 3. He only missed it as a warning.
It’s basically an inversion of the action “Chicago” Boston likes to run where Brown will curve from the corner around the center screen at the elbow and get the ball with momentum to drive the lane. Instead, Green will post in the corner with Curry up top and Kevon Looney on the elbow, reversing that lineup. Curry will push his defender (Brown) under the arc, then sprint to the corner as Looney comes in for the shoulder screen that takes Brown off. Because Jayson Tatum has to sit under Green’s post-up and Williams is back in the middle, no one can argue with Curry’s shot.
One solution is to have Tatum become more aggressive trying to put out the green when Curry starts to cut and Williams backs up even deeper. Tatum can do a swimming move on the green when that first screen Looney hits so he can challenge Curry, then Williams (or Al Horford when he’s in the five with a small formation) can drop back into the paint to corral all the lobs that Curry tries to enter Green or Looney by diving towards the edge.
The risk is that Brown is offside, and the Warriors can create a two-on-one opportunity that’s always dangerous, with Thompson or Andrew Wiggins on the weak side all alone when Boston must inevitably rotate a second defender into the paint. Does Udoka want to play this game of cat and mouse with arguably the best side team there has ever been?
The Celtics should be even more prepared for the flow of the Warriors this time around, as they’ve spent this postseason emulating a fundamental tenet of it. Golden State finds its best shots in the wake of its movement, its big ones being the fixed hubs to distribute the ball and letting its cutters carve out space for someone else to slip in.
Boston added some of these principles to their playoff offense, including having ball handlers like Tatum who keep moving after their pass recipient (often Horford) attacked the fence so Horford could crash the defense, then throwing it behind him to a wide-open Tatum replacing him in his place.
So when they start to see Curry, Jordan Poole and Thompson drop the ball and suddenly reappear somewhere else, they won’t be caught off guard. It’s more a question of whether they are sufficiently tuned and ready at all times to deal with it. Everyone knows what the Warriors want to do. Few teams can handle it.
But after seeing Derrick White glide gracefully across the screens against Miami and a deep backlog of Smart, Brown and Tatum navigating everything to take that daylight out of Golden State, Boston is the only team that can survive this Warriors offense. If they want to win the title, they will have to do more than survive. They have a real chance, but after barely going through two elite teams but injured, well-charged and well-rested warriors will be, by far, their toughest challenge yet.
(Photo by Rob Williams and Andrew Wiggins: John Tlumacki/The Boston Globe via Getty Images)