One of the hardest things to measure in basketball is individual perimeter defense. Measuring interior defense is no picnic either, but in general, high shot-block and defensive rebound rates correlate to good overall team efficiency when it comes to preventing points. Teams with good defensive big men tend to be good overall on defense, and teams that lack a defensive anchor tend to give up a lot of points -- not always, but most of the time.
It's not nearly as cut and dry when it comes to the point guards and wing players around the league. Coaching philosophies play a large part in perimeter defense, as does the quality of a team's big men. If you have Dwight Howard playing behind you, you should be able to be more aggressive out on the floor and cut down on open looks. That's theoretical, as this season's Los Angeles Lakers have managed to play bad defense even with Howard manning the middle.
In an effort to rank the best perimeter defenders in the league, I've created a system that incorporates results from some of these various systems.
From Synergy Sports Technology, I generated reports in overall points per play allowed as well as for isolation plays defended and points allowed on those isos. That accounts for three of the six factors. From 82games.com, I used team reports on PER allowed by position for factor No. 4. For No. 5, I used Jeremias Engelmann's regularized adjusted plus-minus (RAPM). And from my system, I added together percentages in blocks and steals, which is often correlated to good individual defense.
I also used lineup analysis from my system to identify which spots players have occupied this season. A player must have logged at least 400 minutes this season and played one of the three perimeter spots at least 30 percent of the time. That's a little tricky because of combo forwards like Josh Smith and LeBron James, but I ultimately attempted to be more inclusive than not. There are 172 players who qualified for the rankings.
The isolation data is particularly telling for a couple of reasons. First, when you think of the term "stopper," you have an image of a guy facing up with someone like Carmelo Anthony on the wing and digging in while Melo jab steps and head fakes before settling for a fadeaway jumper that clangs off the back of the rim. This is the stopper's job, and the essence of individual defense.
More than that, you can tell a lot by how often a player is isolated on defense. If a guy can't play defense, teams will find a way to go at him. You have to be careful, because sometimes teams are very good at hiding poor defenders, who aren't left to fend for themselves often. The final formula is a weighted average of the rankings in the six factors. The plus-minus data is weighted the most heavily, followed by the Synergy data and steal-plus-block percentage.
Here are this season's top 10 perimeter defenders:
1. Josh Smith | Average rank: 17.94
Smith is certainly athletic enough to guard any position on the floor, though it's questionable whether he is a true perimeter stopper because of the amount of time he spends at power forward and guarding the rim. According to my system, he has played 33 percent of his minutes at small forward this season. He ranks sixth on a per-possession basis against isolations and second in steal-plus-block percentage. Smith is just a really good defensive player, which hasn't always been the case during his career.
2. Andre Iguodala | 21.31
This ranking is true to Iguodala's reputation, as he is a big part of Denver's improved perimeter defense. Iguodala always draws the opponent's top perimeter scorer in crunch time, so he gets isolated fairly frequently. He ranks seventh in points per play allowed against isos, and fourth overall, so it's never a winning strategy to go at Iggy. He leads the league in RAPM.
3. Mike Conley | 22.88
The Grizzlies are one of the top defensive teams in the league, and it starts with Conley's ability to delay opposing point guards from getting into their half-court sets and his thievery in the passing lanes. Playing alongside Tony Allen, who also made the top 10, doesn't hurt. Teams haven't been shy about isolating Conley, but he has held up well in those situations.
4. Marquis Daniels | 26.44
Daniels has never rated very high by advanced metrics, but this shows why he keeps finding work in the NBA. He is first in points per isolation allowed in our group, first overall in points per play allowed and 19th in RAPM.
5. Tony Allen | 31.00
Allen earned first team All-Defensive honors last season, so his defensive reputation is considerable. These rankings show just how good the Memphis backcourt is on the defensive end. Allen is third in RAPM. His rating is actually dragged down by his No. 99 ranking in what I've termed "defensive isolation usage." Teams have isolated Allen on an average of 12.1 out of every 100 possessions he's been on the court. That simply speaks to the quality of defensive assignments Allen draws from Lionel Hollins.
6. Dwyane Wade | 34.50
Wade doesn't have a great reputation for individual defense, and true enough, he ranks just 50th in points per play against isolations. He is sixth overall in PPP and may benefit from always drawing the least crucial defensive assignment when he plays alongside LeBron James and Mario Chalmers. That allows Wade to roam free to collect steals and blocks and save his energy for the offensive end.
7. Luc Mbah a Moute | 34.69
The top perimeter defense belongs to the Bucks, so it's fitting that they land a pair of defenders in the top 10. Mbah a Moute is an old school defensive specialist in the mold of Bruce Bowen. Like Smith, he plays a fair amount of time at the 4, and some of his numbers have been compiled in the paint. However, he has played more than half his minutes at the 3 and is one of the few players in the league who can legitimately guard four, maybe even five, positions.
8. Vince Carter | 35.44
This is easily the most surprising name on the list. Carter didn't have a good defensive reputation when he was at his athletic peak, and he turned 36 a few days ago. He doesn't have a standout category but ranks in the top 40 in each of the five individual factors. The Mavericks haven't been great against perimeter players in general, ranking 25th in opponent PER. Carter, for what it's worth, has improved his teams' defense by 2.1 points per 100 possessions over the course of his long career. This season, the Mavericks are three points better on defense when Carter is on the floor.
9. LeBron James | 37.00
It's no surprise that James shows up in any rankings, but when you consider that he has had to defend the paint more than ever before, this rating is really impressive. You would figure that teams playing big would be able to exploit him on the block. James is rarely exploited on the floor no matter what he's trying to do.
10. Andrei Kirilenko | 39.00
It has to warm your heart when players with great defensive reputations show up in your objective system for rating defense. Kirilenko has long been one of the league's top help defenders, with combined rates of steals and blocks that few perimeter players have ever compiled.
Finally, because I know you're wondering: Ranking 172nd, and last, is Miami's Mike Miller, just behind Sacramento's Jimmer Fredette and the Lakers' Chris Duhon.
Vince Carter
at Duhon being that far on the list. Alright, I guess the list is somewhat accurate
