However, the season was not without its ups and downs. The team’s best four-game stretch came between April 28 and May 18, during which they recorded wins over Mercer and Florida and losses against Boston College (twice). Their adjusted defensive efficiency during this period was an impressive 15%, which falls in the 99th percentile. On the other hand, their worst four-game stretch, between April 14 and April 26, saw them go 4-0 against Pittsburgh, Robert Morris, Louisville, and Virginia, but their adjusted defensive efficiency fell to 28%, placing them in the 59th percentile. The key difference between these stretches was the shooting percentage they allowed, with a 4% difference between the best and worst stretches. This suggests that the ability to limit the opposing team’s shooting accuracy was an especially important factor in their defensive performance.
The importance of limiting shots was also evident in their performance when we narrow in on the 15 games they played against conference peers and teams with similar LaxElo rankings. When the opposing offense took more than 0.66 shots per possession, Notre Dame’s record was 1-5, with opponents scoring on 39% of their possessions. However, when they were able to keep the opposing offense below this threshold, their record improved to 8-1, with an opponent efficiency of just 19%. This highlights the critical role that shot prevention played in the team’s overall defensive success.
Examining the team’s defensive performance depending on the length of the opposing possessions also provides some interesting insights. Notre Dame’s defense was particularly effective in limiting transition and very early offense, with their best performance coming in possessions that lasted less than 20 seconds, where they allowed goals on only 5.9% of the possessions. This is 7.5 percentage points better than the average defense. However, as the possessions got longer, their defensive efficiency dropped, suggesting that opposing offenses were more successful in finding gaps in their defense. On possessions lasting greater than 60 seconds, they were basically a league-average defense. Taken all together, this makes me feel like turnovers were a big part of their approach. You don’t allow 0.51 shots/possession unless at least half of the possessions you face end in a turnover. And teams that were able to make it to the latter stages of the shot-clock had much better success, which makes me think that it was patient offenses with good ball security that were the Achilles’ heel for this team.
All in all, the Fighting Irish defense in 2023 displayed both strength and areas of potential improvement. Their ability to limit shots and shooting percentage were key factors in their success, but maintaining their defensive performance in longer possessions could be a focal point going forward. Overall, their solid defensive rankings and performance against similarly ranked opponents position them as a formidable force in the defensive table.
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P.S. What did I miss? Data-centric analyses like this can miss things that don’t show up in the stats (i.e. injuries/coaching changes). If you can help explain any of the above, put it in the comments.