I went to college in Boston, and while I have some awesome sports memories from my time there (hey there, 2004 Red Sox), it means that to this day there are a lot of Boston sports fans in my life. Yesterday I heard from all of them, mostly words I don't think I'm allowed to reprint on this site. In their version of the Rajon Rondo trade, Dallas got a demi-god in exchange for Dirk Nowitzki's dirty laundry and the loose change Mark Cuban found in the seats of his jet.
Leaving aside their questionable evaluation of Brandan Wright (though not for long! our efforts to convince them that he's awesome will be coming soon), are they right about Rondo? Conventional wisdom says that he's a mercurial player who's strong on defense, has trouble shooting, and plays up (or down) to the talent around him, transforming into the best version of himself during the playoffs. Is that right? Is this what Mavericks fans should expect to see from him this season?
Dallas' most glaring weakness this season has been perimeter defense. Rondo has the reputation of a good defender, but the numbers can help us see where he is good and where he may not be as big a help.
Rondo is good at a lot of things on defense: he's about average in terms of blocks (not so important for a point guard), but he's above-average at steals and good at avoiding defensive fouls. But when you look at his ability to guard shooters, and specifically at the difference between shooters' season-long average field goal percentage and their percentage when guarded by Rondo, things look a little less rosy.
We're a third of the way through this season, but I still think it can be helpful to include last year to get a fuller picture. Here's how Rondo's defense on shooters looks compared to the point guard we're losing, Jameer Nelson. Rondo's opponents this season have shot 7.4 percent better than they normally do from three when he's guarding them, compared to 6.4 percent better when Jameer Nelson is defending:
Last year Rondo was still recovering from a torn ACL, so it may not be fair to judge him on that (he certainly looks better overall this season, and unfortunately we only have defensive tracking data available going back to last season). The Mavericks have been allowing their opponents a league-worst 39.2 percent from three this season, so any trade would ideally include an upgrade in perimeter defense, but it's not clear to me from looking at this that Rondo is quite the upgrade most fans are assuming in this respect.
On top of all of this, the players Rondo guards have also taken more threes, about 1.2 more per game. He plays more minutes than Nelson, but not enough to account for this increase. Just looking at the change in Nelson's defense from last year, when he played for the Orlando Magic, to this year, it seems possible that Rick Carlisle's team defense could be in part to blame, but it's hard to know for sure. It's tough to evaluate these numbers out of context, but there's nothing particularly reassuring about them.
That doesn't mean that Rondo is a bad defender, though! He's good at a lot of things on defense, just not necessarily closing down perimeter shooters. Perhaps Rondo's greatest defensive contribution is his freakish ability to rebound. The average point guard manages about 2.7 defensive rebounds per 36 minutes (Nelson isn't bad; he averages three per 36), but Rondo has been getting an amazing 7.2 per 36 this season. That's more than twice the average! As a team, Dallas has struggled with rebounding this season, so this should be an enormous help. Even if Rondo were to regress toward his career average, we should still expect him to get close to four per 36.
Plus, his Defensive Real Plus-Minus, a stat that measures his impact on the team without the influence of teammates, is 4th best in the league among point guards at 1.34, which is especially encouraging given that his replacement (who usually soaks up some of the influence) is Marcus Smart, a great defender in his own right. So maybe he's doing a little better than people think.
So even though it's not clear that Rondo will help hugely with some aspects of perimeter defense, he should in most respects be a big upgrade. What about on offense?
One of the perpetual complaints about Rondo is his poor (for a point guard) shooting. So far this season, he's made 33 percent of his free throws, which is so atrocious that it seems like it'd actually be tough for a 6'1" professional basketball player to do. This is unusually bad for him, but shooting has never really been his strength, especially his free throw shooting, which has never been above 65 percent. Even the average NBA center manages over 69 percent. This worries some of us:
Just...how good do you have to be at everything else for 42% TS% to not matter? That's astoundingly, jaw droppingly bad. Is he THAT good?— Hal Brown (@HalBrownNBA) December 18, 2014
But I don't think things are quite so bad as they seem. In context, Rondo's shooting looks a little a bit better.
It's definitely true that his true shooting is abysmal. Only twice in his nine-year career has Rondo's true shooting percentage been better than average, topping out at around 54 percent in 2009 and 2010, but it's kind of amazing how much free throws have dragged that down. If you look at his effective field goal percentage (which ignores free throws) he's been above average for five of the nine years he's been in the NBA. Free throws are really important (YGTMYFT and all), but this is somewhat reassuring when thinking about how he'll impact the flow of the offense.
This isn't to say that he's a good shooter (he's really not) but he's a smart player, and his shot selection takes this into account. Over the course of his career, he's averaged fewer than half the number of three-point attempts per 36 that the average point guard does. Even when it comes to his poor free-throw shooting, he seems to be avoiding the tactics that have made guys like Dwyane Wade and James Harden so beloved around Dallas: he only gets 2.9 free throws per 36, compared to 3.5 for the average point guard. So while this is not an impressive shot chart...
... it does show good decision-making, with nearly half of his shots coming at the rim, and it's certainly not like Dallas can't rely on others on the team to space the floor.
Now that we've gotten both the bad and the ugly out of the way, let's talk about something Rondo is amazing at: passing. The average NBA point guard makes 9.3 assists per 36 minutes (Nelson made 5.9); Rondo has made 12.2 this season, and he's done it while keeping his turnover quite low, maintaining at 3.13 assist to turnover ratio. Average is 2.6, and Nelson's was 2.46 during his time with the Mavericks, so this should be a huge boon to an already amazing offense. His ball movement is great too, outside of assists, as he's averaging way more passes per game than any other player, per SportVU tracking data.
The biggest part of the Rondo's mythology is that while he's good in the regular season, he becomes an opposing team's nightmare in the playoffs. Still we have to ask, first, is it true? Does Rondo play better during the playoffs during the regular season? And if it is true, is this unusual or do most players step up their game after the regular season?
Consider this chart that compares Rajon Rondo's career regular season and playoff numbers to the regular season and playoff numbers of all guards who played in the playoffs in 2013-14. It's not a perfect comparison, but it should give us some sense of whether and/or how Rondo plays differently in the playoffs and whether this change differs from other guards (all numbers are per 36 minutes and from nba.com/stats and basketball-reference.com):
On the first question, the answer is a bit of a mixed bag. He shoots threes and free throws a little better, but he shoots so few three-point shots even in the playoffs that I don't think that matters hugely, and his field goal percentage overall dips. In terms of true shooting, he drops from 50.7 percent in the regular season to 48.7 percent in the playoffs, which is pretty common. The playoffs are hard, and most players play a little worse, so while the answer to the first question is hardly a clear yes, Rondo isn't unusual in that respect. You can see how he got this reputation, though: while his efficiency may be down, he puts up more points per 36 minutes in the playoffs, 13.6 over his playoff career compared to 12 in the regular season.
Where Rondo differs, though is his passing. Players tend to be stingier with the ball in the playoffs, shooting more and passing less. Rondo is no exception to this rule (in fact, his increase in shooting is larger than average), but unlike the average NBA guard, his assist to turnover ratio actually improves during the post season.
On defense, there's not a huge shift in his numbers, and we don't have defensive tracking data for any of the years in which Rondo played in the playoffs. But on offense, it doesn't seem like playoff Rondo is a real phenomenon. He's still a good player, though, and any team would be lucky to have him as their playoff floor general; he just doesn't seem to be extra impressive on most measures during the playoffs.
Just as he's been pretty consistent from the regular season to the playoffs, he's also managed to play at a very high level even when not surrounded by a ton of talent. It's true that his best years, in terms of both shooting and holistic measures of his production, correspond to some of the best years of the Boston Celtics (he peaked in 2009 and 2010), but aside from a dip after coming back from surgery last season, he's always managed to play at an elite level, finding ways to compensate for his poor shooting even this season.
All of that said, per the Consistency measure from MMB's Hal Brown at Nylon Calculus, Rondo's "aggregated consistency" is a very inconsistent 0.9. That's not a bad thing, it just means that on any given game he's as likely to kick the game to another gear and go nuts as he is to lay an egg.
Rondo's numbers may not support quite such high defensive expectations in all respects as some fans have expressed, but he should absolutely be an upgrade on that end of the floor, and his poor shooting shouldn't be a huge cause for concern. Fans may be disappointed come playoffs if they're expecting another level from Rondo, but this team definitely just got more fun to watch.
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Hal Brown contributed substantially to portions of this piece.