A deep dive into Jakob Poeltl’s overall impact

When Jakob Poeltl arrived in San Antonio as part of the Kawhi Leonard — DeMar DeRozan trade, many people viewed him as a secondary piece in the blockbuster deal. Three years later, he has nearly turned into the second coming of Bill Russell.

Ok, that’s an exaggeration, but Poeltl has developed into an elite defensive player whose mere presence causes opponents to think twice about attacking the rim. He’s a throwback big man who operates entirely in the paint but has been able to maintain a place in the current run-and-gun league due to his defensive impact, which is especially apparent when we dive into some numbers.

With Poeltl off the court this season, San Antonio has a defensive rating of 113.5, which ranks 22nd in the league. When he plays, that number drops all the way down to 106.7, a figure that would be the best in the NBA. More importantly, Cleaning the Glass omits “garbage time” from these stats, so Poeltl isn’t just helping the Spurs put up empty numbers when games have already been decided.

Of course, it’s worth mentioning that these are team stats rather than individual ones, but Poeltl still ranks in the 89th percentile among all players when it comes to on/off defensive rating. His impact is evident in other metrics too, such as FiveThirtyEight’s overall defensive RAPTOR and ESPN’s Defensive Regularized Plus-Minus (DRPM), where he ranks 1st and 8th, respectively.

If you’re unfamiliar with these stats, they basically estimate a player’s on-court impact on their team’s point differential per 100 possessions. The reason I chose RPM and RAPTOR over more traditional metrics such as Box Plus-Minus (BPM) is because they adjust for external factors such as teammate/opponent quality rather than solely relying on the box score. This helps isolate a player’s individual impact, and RAPTOR even goes one step further by using player tracking as well.

Like most traditional centers, Poeltl focuses his defense on patrolling the paint and protecting the rim. According to Second Spectrum data, opponents are shooting 46.8% within six feet of the basket when Poeltl is the primary defender, the lowest number in the entire league among players who have played more than 10 games this season while defending at least five such shots per game.

One of Poeltl’s most impressive traits is his ability to recover and rotate back into the paint for a block, as is shown in the clip below.

Not only does Poeltl help prevent a step-back three from James Harden, but he anticipates the pass in advance to not get caught flat-footed and switch on to Nicolas Claxton for the rejection. He could even pull this off while running back in transition, preventing Trae Young from converting a layup while saving the ball from going out of bounds too.

It shouldn’t come as a surprise, then, that Poeltl is currently sixth in the league in block percentage at 5.6%. However, like most big men, he does have some trouble staying with smaller guards when isolated against them on the perimeter.

With that said, this is a small trade-off when we take his entire defensive impact into account. The bigger question surrounding Poeltl is his value on offense, and whether or not he contributes enough at the other end of the court.

Poeltl’s offensive value

To stay consistent, we can once again use RPM and RAPTOR to gauge Poeltl’s offensive value. He currently ranks 34th in the league among centers in ORPM (with a value of -2.77) for players who average over 20 minutes per game and has played in over 10 matches this season. That number’s definitely ugly, but it’s worth noting that only eight centers in total have a positive ORPM value since today’s game revolves mostly around perimeter players.

It’s a similar story with FiveThirtyEight’s overall offensive RAPTOR, as they have Poeltl ranked 35th among centres while also sporting a negative value. The good news is that both metrics are still bullish on Poeltl’s overall game since he’s tied for 16th in RAPTOR and 19th in RPM — among players with the same criteria as mentioned before — when factoring both sides of the ball.

Of course, this isn’t to say that Poeltl’s a top 20 player in the league because advanced metrics aren’t able to capture intangible values and both models simply add up each player’s offensive and defensive metrics, which undersells the value provided by shot creators. But it does give us a better understanding of the type of player Poeltl is, which is that of an elite defensive anchor who’s still a negative on the other end of the court.

Fortunately, there are reasons to be optimistic about his offense. For starters, the Spurs are actually scoring two points per 100 possessions more with Poeltl on the court (112.1 on vs 110.1 off), which is essentially the difference between a league-average offense and one that’s ranked in the bottom 10. The discrepancy between his offensive advanced metrics and his positive net rating for the Spurs is probably caused by stats that are hard to incorporate into box scores. One such example would be screen assists, which Poeltl currently ranks 3rd in the league by averaging 5.1 per game.

Even if we factor in these other stats, there’s no doubt that he’s still a below-average offensive player, which limits his overall impact on the game. One of the biggest differences between Poeltl and other traditional defensive big men like Rudy Gobert and Clint Capela is his lack of a rim-running presence. On the season, Poeltl has attempted only one alley-oop, while Gobert and Capela have attempted 62 and 55, respectively.

Now, it’s unreasonable to expect Poeltl to suddenly develop an outside jumper or turn into a lob threat, but he could become a more potent offensive player if his free throw and turnover percentages experienced some positive regression back to his career averages. He’s currently shooting a ghastly 37.3% from the stripe, which is the worst mark in the league by over 9% for players who’ve attempted at least 50 free throws this season. That number alone is worthy of an NSFW tag, but the bad news doesn’t stop there; Poeltl’s turnover percentage has also increased from 14.5% in 2019-20 to 18.4% this year, which lands him in the 12th percentile of all bigs.

It’s somewhat of a miracle, then, that he’s still averaging 1.09 points per possession (PPP) when utilized as the roll man in pick and roll situations, which ranks in the 39th percentile among players who are used as rollers at least once per game. If he’s able to increase his free throw percentage back to his career average of 51% and drop his turnover rate back down to around 14%, Poeltl should become one of the better roll threats in the league.

This will undoubtedly help his individual offense, but the Spurs can benefit greatly too. If opponents start respecting Poeltl as a roller, they’ll focus more attention on packing the paint, which will open up passing lanes to teammates. He can then kick the ball out to shooters or find cutters using his improved playmaking. Poeltl isn’t an elite passer by any means, but his assist percentage has almost doubled since his last season in Toronto, going from 5.5% in 2017-18 to 9.9% this season.

Take the clip below, for instance. Poeltl’s improved offensive awareness is put on display as he passes right back to Dejounte Murray instead of forcing up a shot with the clock winding down.

Even if Poeltl’s free throw shooting or turnover rate doesn’t improve, he’s still established himself as a top ten defensive player in the league and is undoubtedly a vital member of the Spurs’ young core. He likely won’t ever be a positive on offense, but if Poeltl can take better care of the ball and shoot over 50% from the stripe, there’s a chance that he could develop into an an above-average starter instead of just a good role player for San Antonio.