MIAMI — The most important play in a game isn’t always the one you remember most. Sometimes, it’s subtle and doesn’t even make the highlight reel. Sometimes, something as simple as a change in possession can be more important than a shot that does or doesn’t go in.
The NBA has a way to use analytics to figure out just which plays had the biggest impact on a close game. It’s a “leverage” model that was developed to evaluate and instruct referees by pointing out which calls or no-calls had the biggest impact on a game’s result.
Here’s the idea: At every point of a game, each team has a certain probability of winning. Putting the quality of each team to the side, when the game tips off, the home team has a 60 percent probability of winning and the road team has a 40 percent probability of winning. After the first basket, those numbers haven’t changed much. But if the home team is up 10 with the ball and five minutes to go in the fourth quarter, their win probability (WP) is obviously a lot greater than 60 percent.
So, by calculating win probability both before and after a play occurs, it can be determined just how important that play was. Score, possession and location are the factors. And obviously, plays in the last few minutes of the fourth quarter (or overtime) in a close game are more important than any others.
Using the league’s data model, we’ve determined the 10 most important plays made by the Miami Heat or San Antonio Spurs on their way to The Finals.
10. +18.7 percent – Conference semis, Game 5 – Heat get multiple stops on the Bulls’ final possession.
With 26 seconds left, Miami up by three (94-91) and Chicago in possession, Miami had an 81.3 percent WP. After the inbounds, Nate Robinson advanced the ball and attempted a 3-pointer with 18 seconds on the clock that was contested by Norris Cole. Just before the shot, Miami had a slightly better chance of winning (83.6 percent) than at the start of the possession because eight seconds had run off the clock.
Had Robinson’s shot gone in, Miami’s WP would have dropped to 60.3 percent (about -20 percent) with the tie, possession and about 18 seconds left. Instead, the shot missed and the Bulls got the rebound. With just three seconds left, they set up Jimmy Butler for another 3-point attempt to tie.
At that point, Miami’s WP was up to 95.5 percent, but had Butler’s shot gone in as time expired, sending the game to overtime, Miami’s WP would have been cut from 81.3 percent at the start of the possession to about 58.3 percent at the start of OT (-30%). Instead, the shot missed the series was over.
9. +18.9 percent – Conference semis, Game 1 – Boris Diaw hits a three with 2:27 left in the first overtime
With 2:49 left in the first OT, Diaw rebounds a Draymond Green shot that could have given the Warriors a five-point lead. With possession and down three (111-108), the Spurs WP was 28.1 percent. After they advance the ball and swing it around, Manu Ginobili drives into the paint, draws Diaw’s defender, and hits him in the corner for an open three. Diaw drains it, increasing the Spurs’ WP to 46.9 percent. They went on to win in double-OT.
8. +19.0 percent – Conference semis, Game 1 – Dwyane Wade’s steal sets up LeBron James’ three-point play.
With 7:18 left in the fourth quarter, Miami leading Chicago 70-69. and the Bulls in possession, the Heat had a WP of 57.4 percent. At 7:07, Wade steals a pass from Marco Belinelli, increasing Miami’s WP to 64.8%. That’s a jump of +7.3 percent just for the change of possession. But Wade then gets the ball to James, who is grabbed around the shoulders by Butler and still manages to hit a shot with his left hand at 7:04. He makes the free throw, increasing Miami’s WP to 76.5 percent. But the Bulls would come back to win the game, 93-86.
7. +20.9 percent – Conference finals, Game 1 – Chris Bosh gets an and-one tip-in
With 1:20 to go in overtime, Miami is down 99-96 when James rebounds a Lance Stephenson miss. At that point, their WP is 24.5 percent. Bosh misses a three, but James gets the offensive board and sets up Shane Battier for another three. At that point, the Heat’s WP is down to 23.3 percent.
Battier misses, but Bosh rises over Roy Hibbert, gets fouled by Paul George, and tips in the miss. The tip-in with no foul would have increased Miami’s WP 32.8 percent, but when Bosh ties the game with the free throw, Miami’s WP increased to 45.4 percent, for a total possession increase of 20.9%. The Heat went on to win with a play that’s further down this list.
6. +21.3 percent – Conference finals, Game 1 – Cole steals inbounds pass
This was a judgement call as to whether there was a change of possession, because Cole never really had control of the ball, but the scorer tallied it as two successive turnovers.
With the Pacers down three and 10.8 seconds left in OT, George Hill drops the inbounds pass and Cole gets his hands on it. There’s a scramble for the ball at the mid-court line and Hill gets the ball back. He gets it to George, who is fouled by Wade on a 3-point attempt.
Before the play, the Heat’s WP was 71.8 percent, and the first change of possession increased it to 93.1 percent.
5. +22.5 percent – Conference semis, Game 1 – Diaw steal leads to Danny Green lay-up
With the score tied at 111 and 2:08 left in overtime, the Spurs’ WP was 46.6 percent, because the Warriors have possession. But Diaw steals a Draymond Green pass in the lane and gets the ball to Tony Parker, who finds Danny Green for a lay-up with 2:02 left. The steal increased the Spurs’ WP to 59.3 percent and the basket increased it to 69.1 percent.
So Diaw made two huge plays in the Spurs’ Game 1 win over the Warriors. But there were two bigger…
4. +22.6 percent – Conference semis, Game 1 – Danny Green’s three ties the game in regulation
Down three with 29 seconds left, the Spurs’ WP was 22.4 percent. But they run a great misdirection play to get Green an open three from the right wing. He makes it with 20.8 seconds left, increasing their WP to 45.0 percent.
3. +23.6 percent – Conference semis, Game 4 – James’ steal leads to Wade’s three-point play
This one is interesting, because there were still six minutes left in the fourth, but it was essentially a four-point swing, because the Pacers scored about a point per possession in the series.
With the Pacers about to inbound the ball with exactly 6:00 on the clock, the score was tied at 83 and the Heat’s WP was just 41.9 percent (because they were on the road and didn’t have possession). But James steals George’s awful inbounds pass and gets the ball to Wade, who gets fouled by David West and goal-tended by George.
The steal itself increased Miami’s WP to 50.5 percent and the three-point put it at 65.5 percent. But the Pacers would recover and win the game.
2. +61.3 percent – Conference semis, Game 1 – Ginobili’s three wins it in double-OT
With the Spurs down one with 3.4 seconds left, their WP was 35.7 percent. Ginobili’s three left 1.2 seconds on the clock, but increased their WP to 97.0 percent.
1. +77.6 percent – Conference finals, Game 1 – James’ game-winner
From 22.4 percent to 100 percent.