Nylon Calculus: Celtics-Bucks win probabilities, style, matchups and more
By Justin
The Celtics will be without Kyrie Irving for the playoffs, and for most teams this would be cause to write them off for the postseason and edge toward the lower seed. But it’s tough to count out this Brad Stevens squad. They regularly fool people with their win totals, and outperform expectations no matter who’s on the roster. While the team will surely struggle to muster up a decent offense without Irving, their defense alone should be enough to propel them forward for at least a round (and, honestly, the defense will be better without him.)
One of the keys to their defense? They led the league in opponent 3-point percentage, and in a world where that shot is becoming a larger part of basketball this has become increasingly valuable. Given that the average team takes 29 of those shots a game, a one-point percentage decrease translates into a savings of 0.9 points per game. I’ve discussed the noise about this stat before, and how hard it can regress to the mean. Yet Boston improbably has been top five in that stat since 2008, finishing first this season by a hair over the 76ers. You can see that in the graph below; they’ve been on the outer edge of opponent 3-point percentage for a decade. I’m not exactly sure what’s in the water, but even against the Bucks, who take few outside shots, it’s still a significant advantage.
— Justin Willard (@AcrossTheCourt)
Defensive matchups
Giannis Antetokounmpo is a challenging matchup for any opponent, and perhaps no team understands that better than the Celtics.
Antetokounmpo has enjoyed yet another stellar season, taking a step forward in his already impressive career. His 27 points per game are a career-high, driven by an increase in minutes (from 36 to 37) and usage (from 28 to 31 percent) alongside consistent efficiency: both his effective field goal and true shooting percentages are steady at 55 and 60 percent, as is his turnovers per 100 possessions at 4. Consequently, according to ESPN’s Real Plus-Minus, his overall impact continues to hover around the top 10.
As notable as these numbers are, they’ve been even more impressive against the Celtics. In their four regular-season games, Antetokounmpo averaged 34 points on 62 percent true shooting and 38 percent usage. This latter figure represented his second highest usage rate against any team this season and highest against any team that he faced more than twice. Indeed, three of his five highest-usage games came against Boston. He was particularly productive in the restricted area, where he took half of his shots and made 78 percent, six percentage points higher than his average for the year.
The following chart shows how the Celtics matched up defensively against the Bucks in these games. Each line indicates the defender who spent the most time guarding a specific offensive player on a given possession. The thicker the line, the more frequent the matchup.
Al Horford has been identified as the primary defender on about 45 percent of Antetokounmpo’s offensive possessions. Expect the same in the first round, especially with all of the Celtics’ injuries — although, of course, with some schematic adjustments from head coach Brad Stevens.
— Positive Residual (@presidual)
Offensive styles
These charts are not meant to evaluate whether an offense is good or bad. They are designed to help illustrate how teams go about the goal of trying to put the ball in the basket. Each team’s offense is evaluated on four stylistic spectrums.
Ball movement is measured with the average touch time for each team, from the NBA’s player tracking statistics. A lower average touch time means the ball is moving from player to player more quickly.
Player movement is measured with a combination different NBA.com tracking statistics, and works out to average distance traveled per 24 seconds of offensive possession.
Pace is measured with the average length of an offensive possession from Inpredictable, a more accurate representation for how quickly a team is working than traditional pace.
Shot selection is measured with MoreyBall percentage — in this case the percentage of a team’s true shooting opportunities that came at the rim, from the free throw line, or on a 3-pointer. It’s a generalized measure but captures something about how much each team hews to the shots that are, on average, the most efficient.
On the graph below you’ll see a line for each team’s offense. As the line moves away from the center of the graph on each axis you’re seeing more of that stylistic trait. For example, shot selection shows a (hypothetically) more efficient shot selection the further you are from center. Here’s how the Celtics and Bucks match up.
These two teams play very similar styles, with the Bucks pushing the tempo slightly more. It’s interesting that Boston’s level of movement has retreated dramatically this season with the incorporation of Kyrie Irving. It’s possible that their style moves in the other direction with him out., towards more of the free-flowing offensive style they used last season.
— Ian Levy (@HickoryHigh)
Win probabilities
To project the series, I am using my in-season game projection model. The model is trained off historical game data, and accounts for rest, travel, team strength, and matchup. Since I began using the model to predict outcomes, I have been able to correctly identify the winner in about 70 percent of games.
The Celtics come into the first round with about as bad a bill of health as is possible for a No. 2 seed. This series will be a complete clash of styles, with the organized and disciplined Celtics going against a Bucks team that occasionally looks entirely lost and confused on the court. This series features one of the largest upset potentials, with the Bucks single-highest outcome, winning in six games, occurring nearly as often as either of the two Celtics highest outcomes. The series will come down to how the Celtics young stars, Jayson Tatum and Jaylen Brown, are able to handle a playoff series as lead options. This series is nearly tied with the Thunder-Jazz series and Blazers-Pelicans series as the most likely to go to seven games, occurring in over 30 percent of simulations.
— Jacob Goldstein (@JacobEGoldstein)