Originally Published on December 15, 2018

Indiana just beat Butler on this absurdly lucky 35-foot heave.

(Broken Link)

Phinisee should have never been allowed to get that shot off…because Butler should have fouled IU.

Here’s the situation and some back-of-the napkin math. YES it was a lucky shot for Indiana, but luck is factored into the percentages below.

#1 If the game goes to overtime, on a neutral floor with two nearly identical teams, there is a 50% chance of victory for each team.

#2 Indiana had a 45%-ish chance of winning in regulation. (Let’s say 90% chance at a shot x 40% chance of either a score or a shooting foul + 30% OREB (insert recursive function)). We don’t care about threes bc we assume they get the last shot.

#3 So if IU had a 45% chance at victory in regulation and a 50% chance in OT if it made it that far, Butler only had an approximately 27.5% chance of victory by not fouling.

Let’s say inside that Butler chose to foul.

#1 You have a fairly non-zero chance at forcing a TO. You do this, the odds invert and Butler has a 75% chance at victory. But we will lay this aside for now.

#2 The players on the floor for IU’s FT % (Career):

Juwan Morgan: 66%

Romeo Langford 69% (small sample but watching his shooting stroke as a freshman in this environment seems high)

Rob Phinisee: 69% (Small sample, 11–16)

Justin Smith: 65%

Devonte Green: 72%

#3 So all 5 players on the floor shoot ~ 70% from the FT line.

#4 The math is as follows:

30% chance they miss the front end, you get the ball in a tied game and odds invert (OR chance here is low)

21% chance they get 1 point

49% chance they get 2 points.

#4 so multiplying it out, and again, assuming with that much time left that securing possession inverts the odds, the probability tree is as follows. Also, this eliminates threes for IU and puts them into play for Butler.

BU Ball, tie game in regulation, 10 seconds left. Win probability 77.5%*30% chance of occurring=23.25% chance of BU Victory

BU Ball, down 1, 10 seconds in regulation.

(Win probability: 35% *21% likelihood=7.4% chance of victory

Tie probability with OT: 10% (round number guess))*21% likelihood*50% OT= 1% chance of victory

BU Ball down 2, 49% chance of occurring *30% chance at tie * 50% OT =7.45% odds

You also have non zero odds at scoring one and fouling IU, who is still in the 1 and 1, with you down 1. And you can hit a three, while eliminating IU’s ability to do so!

But ignoring that #, we still get summative odds of Butler Victory if they fouled of:

39.1%

If someone can spot some math errors or assumptions that you think are wrong, let me know. I did this on a piece of paper in 15 minutes, but I believe the odds conclusively show that Butler made a grave mistake (~17% expected EV chance). This is a scenario that EVERY team should be modeling and prepared for.

Btw, yes, I know IU had a foul or two to give but colleges rarely if ever execute fouls to give properly. Fouling on the correct play to send a guy to the line is easier than coordinating 2 fouls but not 3 in front of 18,000 fans with 2 freshman on D, against guys like Sean McDermott who will have the wherewithal to shoot on the catch. Fouling on the catch for a team waiting to shoot is much, much easier.

Why Butler Should Have Fouled in a Tie Game