The Herro Rules

Thirty-seven points in Game 4. Twenty-two in Game 3. Nine for his last twenty-two from deep, but more importantly 13-from-17 from inside the line, with seven assists, just two turnovers, and going 6-6 from the line.

Tyler Herro isn’t just a shooter sparking things up with a hot streak from deep like his teammate Duncan Robinson. He’s using his shooting prowess and the necessity of Boston going over-the-top of screens to leverage openings in the lane, too. He’s taking advantage of getting Celtics defenders on his back and blistering them with mid-range pull-ups.

Now in a 3-1 series hole, the Celtics need to revisit their game plan fast. They can’t simply rely on water reaching its level and Herro cooling off. They need to take matters into their own hands, and that means devising a game plan more specifically tailored to limiting the rookie.

How might they do that? We’ve got a couple of ideas that illustrate tangible moves--supported by data--which could tip the series back in Boston’s favor.

Photo by Jim Poorten/NBAE via Getty Images

The Herro Rules

When Synergy Sports, the most available in-depth data on player tracking and shot attempts, labels player shots out of pick-and-rolls, they talk about where the screen was set on the floor (middle, left or right) and if the player used or refused the screen. That labeling system doesn’t allow for analysis of whether a player is better being pushed to his right or to his left, as screening angles aren’t documented in the data.

So, through both regular season and playoffs, I went through and watched every dribble pull-up Herro has taken out of ball screens and handoffs inside the bubble to get a feel for that myself: is there a definitive direction where he’s less impactful as a scorer and “weak” coverage that can be deployed?

The results were pretty staggering.

Even accounting for a breakout performance in Game 4 where he couldn’t miss going either direction, Herro is far more consistent a pull-up shooter when going to his right hand. When he goes to his left, things get a little more dicey. Due to his shorter wingspan, long defenders can get closer to interrupting his shot, and that impacts the quickness and fluidity of every jumper:

As he’s become Miami’s hottest scorer and one of their most lethal threats in the playoffs, now may be the time for Boston to focus the game plan on him and write The Herro Rules.

Such rules need to be more nuanced than a simple “force him left” approach. The Celtics’ entire defensive identity has been built on 1) not allowing middle, 2) icing ball screens, and 3) keeping penetration to the outer-third. When Herro is on the left side of the floor, this is a natural fix for the Celtics, as two core defensive principles align, but when Herro is on the right side or in the middle, Boston has seen mixed results forcing him left.

Players who are best-equipped to bother Herro here are the ones who have a length advantage and can crowd him without giving up a speed advantage. The perfect possession on his middle screen-and-rolls comes from jumping to the right early, making him refuse screens and go left, then riding his right shoulder so he doesn’t have enough room to get his jumper comfortably off:

Jaylen Brown should be able to replicate OKC’s Andre Roberson’s defense against Herro, using his length and high-IQ to funnel the ball towards the left elbow, but discipline is required to avoid biting on ball fakes and not let the ball get back to the right side.

Brown lost that focus in Game 4 during moments when the Celtics aimed to push Herro left:

Stevens and his staff have to determine if they want to force Herro middle on true pick-and-rolls occurring on the right side of the floor. To ice them would put Herro to his strength, but to do something different interrupts their continuity and strategy they’ve built a top-five defense upon all season. It becomes even more difficult when the Celtics must trust one of their backup centers to do the deed, all of whom lack experience or quickness.

Ball screens aren’t the only area to hone in on. While the disparity in terms of efficiency on dribble handoffs isn’t as high, the effect of these handoffs is the same. He’s an incredibly dynamic scorer with a live dribble on his right side (with a great hip turn), but when he goes left, the shot isn’t quite as smooth and doesn’t have the same balance:

Miami has done a great job of placing Herro in these situations to come to his right. Notice that when they have an inbound on the right sideline, Boston goes into a 2-3 zone. Miami puts Herro in that right corner, empties that side out, and engages him in a handoff anyway, either challenging the zone to stay with him and morph into man or cede an easy jumper in his wheelhouse.

So what exactly are The Herro Rules? When a handoff is ready for him coming to his right, deny him and force him backdoor. When it’s coming to his left, trail him, and contest from behind or towards the right shoulder. In ball screens, force him to his left when on the middle or left sides on the floor.

On the right side, I’d encourage mixing up coverages and trying this next strategy on for size.

To trap or not to trap

The blessing of Synergy Sports, when used correctly, is that it can illuminate certain statistical blemishes on a player’s profile. For Herro, the pick-and-roll has been his least efficient mode of scoring. During the regular season, he ranked in the 25th percentile as a PnR ball handler, averaging only 0.71 points per possession; he’s been better in the playoffs (44th percentile, 0.89 ppp), but much less effective than off DHO’s.

When the defense decides to trap, his lack of length and the few shooters Miami surrounds him with are evident. If scoring from Herro is the worry, the most effective strategy to prevent him from scoring is to simply get the ball completely out of his hands without having to learn a unique defensive strategy on the fly:

In trapping situations this year, Herro turned it over 20 percent of the time, and teammates only shot 1-for-9 when the ball found them. Statistically-speaking, he may be the right guy to trap.

Herro has played 130 minutes this postseason (10 minutes per game) sharing the floor with both Bam Adebayo and Andre Iguodala. While both are talented passers that make high-IQ reads and the right play around Herro, their presence would enable the Celtics to shrink the floor when trapping the rookie scorer. Adebayo, the likely screener, stands in the middle and catches the ball for a momentary 4-on-3. Iguodala’s man should help heavily, leaving the man who is 2-for-11 on treys in his last six games.

Iguodala played 27 minutes in Game 4 as the Heat pivoted away from Kelly Olynyk and towards a more mobile, playmaker-centric lineup. If Miami is going to put non-shooters on the floor around Herro, Boston should turn him into a facilitator and ground him from taking flight.

Of those 130 minutes the trio shares, a little more than half of them (68, to be exact) come with Jimmy Butler, another inconsistent deep threat, on the floor. These lineups scream “blitz Herro” - even if he isn’t overwhelmingly hot from the field. Trapping can’t be done recklessly, especially with three incredible passers on the floor, but a preventative approach to the Herro assault may be the right one.

The biggest obstacle to trapping, especially on the right wing, would be in the drastic departure such a strategy would have from their normal coverage of icing ball screens. Icing pushes the ball handler away from the screen, while trapping only succeeds if you push him towards the screen. Rectifying that situation and weighing the pros and cons of changing their base defense with giving away their plans before the screen is an unenviable task for Stevens and his staff.

Lineup Maneuverability

The return of Gordon Hayward to the rotation has given Stevens a few more wrinkles he’s able to throw at teams. The super-small lineup late in games has been featured, as have some offense-for-defense substitutions involving Daniel Theis and Kemba Walker late in games. Stevens knows infinitely more about this team and the strengths of each player than I do, so substitution patterns are something I try to avoid critiquing.

But looking forward to Game 5 (and hopefully beyond), Stevens could make the decision to match Marcus Smart’s minutes more closely with Herro, pulling Hayward back into the starting group and returning Smart to the bench role he once thrived in. Offensively, Boston features a little less balance by putting Hayward with the Big Three from the jump, but it’s a defensive-minded adjustment which thinks more about matching Miami’s bright young reserve.

Smart is as smart and pugnacious as they come (having minimized Goran Dragic’s early production in the series), and his ability to execute a nuanced game plan like the one mentioned above could be the ace in the hold Boston relies on.

Having your back against the wall is never a comforting feeling. The Celtics must win three straight to return to the NBA Finals, and do so against a veteran-laden team that doesn’t beat themselves. To be the optimist, the Celtics have been there in every game during crunch time, and the wrist injury to Bam Adebayo could be a factor that swings this series.

However, Herro has made himself a priority for the Celtics and now is the time to ensure Herro doesn’t become a villain in the lures of Boston sports history.