Was C.J. McCollum Correct When He Called Avery Bradley ‘The Best Perimeter Defender In The League’?

This could be our favorite overstatement from Friday night’s surprising result in Oakland.

Trail Blazers guard C.J. McCollum has experienced a career year for Portland this season, but he wanted to celebrate one of his peers on Friday night. McCollum was watching with the rest of the NBA when the Warriors finally lost at home to the Celtics, and he decided to publicly show his appreciation for Celtics guard, Avery Bradley — he of the pesky, on-ball defense for 94 feet.

Now, to McCollum’s credit, he answered many of the resulting guffaws at the proclamation, and responded to most of the other players — Tony Allen, Kawhi Leonard, etc — who were mentioned in his responses.

Plus, there were more than a handful of people who agreed with McCollum, and one national basketball writer reiterated just how severely “underrated” Bradley was as a defender.

But this is where we #wellactually C.J. like that nebbish kid who was always keeping track of the box score during your high school basketball game. The data just doesn’t support McCollum’s statement.

First, Bradley is ranked 44th among all NBA point guards in ESPN’s defensive real plus-minus (DRPM). For the non NBA nerd, DRPM is basically an estimate of a player’s defensive “on-court impact” measured by how many points his team allows per possession. So it’s basically the team’s defensive rating when the player is on the court, but the “real” part of it uses a formula that also takes into account the prowess of a player’s teammates on the court, too.

So, um, that’s not so good for the whole best perimeter defender in the NBA thing. Then again, real plus-minus isn’t the perfect stat to measure a player’s defensive impact. There isn’t a PER for defense yet, so we have to look at other data before we get to the whole “eye test” scenario basketball fans have been trotting out ever since John Hollinger first cracked open a Bill James book.

But the other numbers we can look at don’t really support McCollum’s claim about Bradley, either.

Avery’s straight on/off numbers are really bad, actually — at least on the defensive side of the ball. The Celtics give up 102.8 points per 100 possessions when he’s on the court and 97.0 when he’s on the bench. That’s the difference between the 12th-best defense and No. 2 defense in the Association. (According to the on/off numbers, the C’s do score a lot more with Bradley on the court, 106.7 on vs. 98.4 off, but McCollum wasn’t talking about his offense.)

Next, there’s Synergy data, which measures how a player performs when the person they’re guarding turns the ball over, shoots, or gets fouled. Again, Bradley is ranked in the 44th percentile, which just deemed “average” by Synergy.

Last is the eye test older players love to talk about because it discounts numbers, which seem to scare older generations of NBA players because new stuff always freaks out older people — that’s part of being old. But even with the advent of PER and other advanced data, there’s no silver bullet accounting for a player’s on-court efficacy. All good basketball analysis is a combination of numbers and watching film. So lets look at the film of Friday night’s upset, which is what appears to have prompted McCollum’s tweet.

His proclamation could have something to do with reigning MVP Steph Curry coughing the ball up nine times in the big Boston upset. But not all of those turnovers were forced because of Bradley alone. Take this one for example.

https://i.giphy.com/l4hLSzcZU1eMi6hby.gif

The way Amir Johnson hedges the high screen so close to the mid-court line is what actually forced Steph into the over-and-back whistle.

Or, Steph simply slipped up:

https://i.giphy.com/xTiQywWnqbU29NIqTS.gif

Maybe McCollum was talking about Steph shooting only 1-of-5 in that final session, including two misses in the final minute, one of which could’ve tied it up with just a couple of seconds on the clock. But after reviewing the film, Isaiah Thomas was the one guarding Steph for the majority of his shot attempts in the final quarter, and Bradley only really defended him on one missed corner three-point attempt.

https://i.giphy.com/3oGRFfuHNm3XLvEnYc.gif

This is not to say that Avery Bradley isn’t an amazing defender and a deserving candidate for an All-Defensive selection when the season ends in less than two weeks. But he’s not the best perimeter defender in the NBA. Sorry C.J.