Midway through the fourth quarter of Monday’s game between the Toronto Raptors and Philadelphia 76ers, Lou Williams brought the ball up court, accelerated toward the basket in an attempt to score before settling into a post up near the left back. With Ish Smith guarding him, Williams took a few dribbles in place before taking an angled dribble toward the free throw line, leaped into the air and sunk a fading 10-foot jumper.

It was a basket that continued to hold a feisty 76ers' team at bay, but was an isolated event in the grand scheme of the game, as Williams, who finished the night 6-of-15 from the field, was hardly on some unstoppable roll. Yet despite this random occurrence, Philadelphia coach Brett Brown decided off that one play that the Williams-Smith matchup was untenable for his side. So with the Sixers clinging to the faintest of hopes, late in the fourth, this happened:

It was another example that could be added to the discussion about how teams in today’s era of advanced analytics should go about defending post up play. And brings back an increasingly popular question: Why do NBA coaches use double teams so much?

The Smoking Gun?

Last year, I researched and wrote on the efficiency of post ups and came to the basic conclusion that the threat of a dominant scorer on the low block is actually more valuable than his individual production out of the action. And thanks to Synergy Sports data, we have empirical evidence that helps illustrate that point.

Here is a table of the top 10 players [minimum 50 attempts] and their Points Per Possession (PPP) on pass outs -- situations where they receive the ball on the block and move it to a teammate cutting or spotting up -- from post ups.

PPP Pass Out.png

Now while once again paying attention to the far right hand column, look at the difference in PPP on the Top 10 most effective post up players [minimum 100 attempts] when they look for their own offense.

Post Ups.png

Like most data, this can’t be used to definitively state passing out of the post is always a better play than shooting out of it, but it’s pretty damning nonetheless. Portland’s Wes Matthews, the best post ‘scorer’ of the group, would fail to even crack the top 10 of players whose best post up work comes from drawing the defense in and kicking out to open teammates.

In the specific case of Williams, he’s a good isolation player (Post ups and isolations are essentially the same and sometimes the data collection by Synergy is inconsistent in defining which spots on the floor qualify as which action. Synergy is still awesome by the way.), averaging .98 PPP on 205 charted attempts, but hardly an unyielding and physically overwhelming force. So choosing a tactic to bring an extra defender to the ball -- a move that causes chaos behind the play and can be exploited by the great ball movement the Raptors had -- is a curious one to say the least, especially after Williams scored just once in a similar situation.

As I pointed out in Hawk, this isn’t meant to pick on Brown or the Sixers. And it’s certainly not meant to harp on one play in a relatively meaningless game. Instead it’s a great example to further the discussion of why Brown and NBA coaches like him seem trigger happy when it comes to double-teaming perceived mismatches in the post. So despite the data, all of which is accessible (and probably in greater, more individualized detail depending on the organization) suggesting it’s generally better to let opponents live and die by 1-on-1 battles in the post, why does stuff like this still happen? Well for starters, it’s because coaches wouldn’t make very good poker players.

Betting on Long-Term Trends

Anyone that’s tried to play poker for a living knows that his or her financial future is ruled by probabilities. Despite general notions born from basement poker nights and Hollywood movies that success on the felt is about feel and luck, it’s really rooted in math, emotional control and conceptual thinking. With every hand, poker players ‘invest’ in a financial edge.

So say you’re playing No-Limit Texas Hold’em and you hold top set (three of kind) in a heads-up pot against a player whose range (poker lingo for the hand combinations a player’s betting pattern suggests he could hold) predominantly includes a flush draw (for non poker people, that’s when you have four of one suit and are hoping to land the fifth). If it’s after the flop (the first three community cards in Hold’em), you will win that hand roughly 75 out of 100 times when the final two cards are dealt. Now while this situation isn’t as cut-and-dried in real poker, the general notion is that 75 out of a 100 is a good deal for you, so you should get your money in when you can. The problem is, however, you’re still going to lose 25 percent of the time you’re in that spot. And to make matters worse, you just don’t know when or where those instances where variance bites you in the ass will occur (or how much it’ll cost you).

But when winning poker players know that a 75 percent edge is available, they take it. Because over the long-term, being the guy holding three-of-a-kind against a flush draw is going to make you a lot of money. Now sure, the flush will hit a few times and make some lucky sap feel like his play was a savvy choice, but in the end, he’ll be broke and you’ll be counting those greenbacks.

The problem for NBA coaches (and losing poker players), is they let short-term outcomes skew what is a smart, long-term approach. NBA coaches know that 3’s, layups and free throws are the shots that beat them and 2-point shots outside of the paint -- like the turnaround jumpers so many players take in post ups -- are the ideal result of every defensive possession. Yet if a player like the aforementioned Williams hits a few shots in a row over a smaller defender, he’ll all of a sudden see double-teams that create the opportunities for the truly efficient shots. It’s the equivalent of coaches seeing a few flush draws hit against their made hand and deciding that chasing the flush is where it’s at.

But one of the biggest reasons so many coaches fall into that trap is because of comes down to one key group: all of us.

LaMarcus Aldridge and Theory Versus Reality

It’s really easy to mull all this over and decide that if you ever become an NBA head coach, you would never double team Lou Williams. And while you may be right there, things get a lot dicer when it comes to some of the league’s premier post scorers, like Portland’s LaMarcus Aldridge.

In light of the way that “efficiency” and “player value” are now forever linked, Aldridge might be the most strangely successful player in the NBA. Up until this year, he never attempted more than 28 3’s in a season (he’s approaching 70). Aldridge also currently ranks 114th in Free Throw Rate, per Basketball Reference data and is hardly going to be confused with DeAndre Jordan when it comes to finishing around the rim. Yet there’s no denying that the dude is a scoring-machine who can, will and has beat teams (Hi Rockets!) by himself if left to do so.

And that’s why coaches chase the flush. It’s a lot easier for a coach to handle fans, reporters, talk radio shows, etc., if his gameplan revolves around letting Blazers not named Aldridge rain shots from the most efficient areas on the floor as long as the All-Star big man isn’t getting his. Saying things like “we tried to take the ball out of his hands” in a losing effort where a player like Aldridge scores 20 points is a lot easier than rambling some long-winded response about variance, efficiency and long-term trends on a night he’s single covered and scores 51. Chances are that if the team playing Portland is evenly matched, the latter strategy will produce more wins than losses over a suitable sample size.

But therein lies the rub. Regular season games are singular entities with paying customers who want to believe their head coach has done everything he could to win that night, not a lot of theoretical outcomes in the future. A playoff series is a best of seven, not a best of 700, and fans don’t take the news a chance at a title was subverted because their coach bets on long-term trends. It’s also to important to remember that like most fans, the players on the team may also not think too highly of another year of their already short careers being over because future situations will statistically produce a better result.

And those outside pressures are why there’s no ‘smart’ answer to the post up debate. The only result that seems overly brilliant is the one that simply works at the time. But maybe one day data will eventually change the way NBA coaches approach defending the post. I just wouldn’t bet on it.