I feel as though I need to speak up against this trade because I’ve been one of Rajon Rondo’s strongest critics for a long time. For example, here’s an older article about how deceiving Rondo’s stats are given that Boston’s offense has usually been just fine without him. The most famous instance is 2013 where the Celtics were playing poorly, they lost him to an injury, and they made a run and eventually made the playoffs. Adjusted for strength of schedule, the Celtics were 2.3 points per 100 possessions better on offense in games without Rondo, which is bizarre because he was replaced with Avery Bradley. Plus/minus models agree that he’s overrated too, estimating that he’s usually a neutral player (mostly in recent years) and far from the star his reputation suggests. But Dallas is one of the most forward-thinking organizations out there and one that uses a lot of advanced statistical measures. What are we missing?
A year ago, Dallas was derided for signing Monta Ellis, a consolation prize after striking out with more notorious free agents. Those in the stats world of the NBA scratched their heads and even openly mocked the move because Ellis was, for lack of a better term, a chucker who tossed up terrible shots. But in Dallas with a great coach and capable teammates he found himself open more often and his aggression at getting to the basket was appreciated.
However, some of my reservations remained: Dallas was already going to have defensive issues, and they paired Ellis with Jose Calderon. The Mavs used a big chunk of their cap to bring in a player who wouldn’t help them become great but just good enough to make the playoffs. Dallas’ defense was fairly awful, and Ellis was culpable. He was better offensively, yes, in their system, but what did they really win?
Bringing in Rondo is bizarre for a team that’s already performing at a really high-level on offense. Looking at offensive rating relative to the league average, Dallas is close to plus 10 points, which is utterly crazy and it would be a record if held for a full season. Rondo is not an off-ball player and he needs the ball in his hands. He’d hurt the team, in fact, by standing on the perimeter because there’s no reason to guard him out there and all the reason in the world to crowd Dirk or Ellis. So you’re handing over the reins to the league’s leading offense, and one that nearly led last season, to another point guard, one who’s struggled after injuries and is on track for one of the most inefficient seasons ever, much less for a guard. It’s like Dallas is doing a “heat check” after the lukewarm success with Ellis and convinced themselves they can change Rondo.
The problem is that we haven’t seen Rondo at his best in a long time, not since before an ACL injury. He’s almost 29 years-old and he’s a non-shooter who relies on a lot on his athleticism. Those are glaring warning signs of impending doom at a player who could suddenly and swiftly go under.
Rondo doesn’t properly address their defensive problems either. It’s been a long time since he’s been a plus defender. Opponents are shooting better when Rondo is the nearest defender, and what’s most interesting is how low the expected FG% is of the players he’s defending. Basically, he gets a lot of easier defensive assignments now. The team is defending a little better with him off the court. When he came back last season, Boston’s defensive rating dropped by four points. He’s a rebounder stealer too, and those who think he’s going to help Dallas rebound should consider how contextual rebounds are.
Dallas, however, sees something in him. The talent is evident because he moves like no other human being on the court and makes difficult trick passes. Perhaps they think they can turn him into the defensive pest he once was while passing and dishing to every corner on offense. I just don’t see it. And Dallas gave up their backup center, one with a 76.2 TS%, which would be by far the greatest season by shooting efficiency ever, for a guard with a TS% of 42. Rondo can’t even make free throws anymore, and when you’re afraid of contact for fear of getting to the line you can go the way of Biedrins and become a liability. And they have no good backup for the brittle Tyson Chandler.
Some statistical metrics disagree with Rondo because he does a lot of things that show up in countable stats like steals and the combination of assists and rebounds that correlate well with being valuable, but “pure” plus/minus only models don’t find that same impact. A lot of metrics today use a Bayesian method where you adjust your bet by assuming players doing X with a certain stat are at a certain level of value. This is a generality and works with a large group of players, but it can whiff on a few cases. I’m sure there’s something in the numbers that Dallas loves, probably to do with his steal rate and rebounds at the point guard position, but I think most of his numbers are misleading.
There’s some talent left in Rondo and he can certainly do a few positive things, but he’s getting old and injuries have stolen some of his gifts. It’s a wonder how he’ll play next to Ellis, someone who needs the ball in his hands too, but Dallas is somehow convinced. Maybe it’s the allure of a star player, something that’s eluded them for years in free agency. But Rondo’s no star, certainly not now.
Rondo can still lead the league in assists per game, but Dallas already has the best offense not just in the league but NBA history — so who cares? They think they can revitalize Rondo, probably on defense, and time will tell.
I’m waiting with skepticism.