While ESPN's new real plus-minus (RPM) is useful at both ends of the floor, it's disproportionately useful at the defensive end because so much of what makes for good defense can't be captured by the box score or even necessarily credited or blamed on an individual player on a single play. To wit, my WARP rating explains half the variation in offensive RPM, but less than 40 percent of the variation on defense.
By capturing the impact an individual player has on his team's defense when on the court, adjusted for teammates and opposition -- along with box-score stats that predict those ratings -- RPM offers a much more complete measure of defensive contributions.
For the most part, current results (which include past seasons, but are weighted more heavily to this season) conform to conventional defensive wisdom. Of the league's top seven players in defensive RPM on a per-possession basis, three have been Defensive Players of the Year, including Kevin Garnett (+5.9), reigning winner Marc Gasol (+5.0) and Dwight Howard (+4.9). Two more, Tim Duncan (+5.2) and Andre Iguodala (+4.9), have been picked for the All-Defensive Team, and Andrew Bogut (+5.0) might join them this year, leaving only league leader Larry Sanders (+6.3) -- whose impressive 2012-13 performance outweighs his disappointing 2013-14 campaign -- as an exception.
As important as RPM may be to evaluating defense, it's still just one of several measures that together can help us assess a player's defensive value. In fact, my Defensive Player of the Year and All-Defensive Team picks for this season, which are based on a combination of stats and scouting, include only two of those top seven players. Let's take a look.
Point guard
Rubio
First Team: Ricky Rubio, Minnesota Timberwolves
Second Team: Patrick Beverley, Houston Rockets
Honorable Mention: Eric Bledsoe, Phoenix Suns; Avery Bradley, Boston Celtics; Chris Paul, Los Angeles Clippers
Last season, I declared that Bradley and Bledsoe were likely fixtures at this position for years to come. This time around, they've been unseated by two more up-and-coming point guards. Rubio, my second-team pick in 2011-12, reclaims his spot after injury knocked him out of contention last season. He leads the league in steal rate, but is also effective one-on-one because of his size and wingspan.
While Rubio might be the best defensive point guard, Beverley is certainly the least fun for opponents. His aggressive on-ball defense, complemented by strength and quick feet, makes him a nightmare matchup. Bledsoe still had the best defensive RPM among point guards (+3.6 points per 100 possessions), but the time he missed due to injury bumps him to honorable mention. Bradley wasn't quite the same defensive presence this season without veterans like Kevin Garnett and Paul Pierce around him. The old vet on the block is Paul, who remains elite in terms of generating steals without taking dangerous risks.
Shooting guard
Iguodala
First Team: Andre Iguodala, Golden State Warriors
Second Team: Jimmy Butler, Chicago Bulls
Honorable Mention: Tony Allen, Memphis Grizzlies; Thabo Sefolosha, Oklahoma City Thunder; Klay Thompson, Golden State Warriors
RPM backs up conventional wisdom by indicating that big men are almost always the most valuable defenders. Iguodala, who ranks sixth in defensive RPM (+4.9) is the exception that proves the rule. His ability to both lock down opponents and make plays as a team defender is unique. Iguodala's impact has been easy to see this season. The Denver Nuggets have crashed from 11th to 21st after losing him to the Warriors, who have improved from 13th to third. Golden State also slumped defensively when Iguodala missed time with a hamstring injury early in the season.
Allen and Sefolosha, perennial All-Defensive contenders who made up my shooting guard picks a year ago, have both missed extended periods. That pushes them to honorable mention and opens a spot for rising defensive standout Butler. The Bulls' new stopper generates plenty of steals and blocks as well. The last honorable mention spot goes to Iguodala's teammate, Thompson, who has improbably become a better defensive player than scorer as a pro. He's especially good when asked to use his length against point guards, a trendy form of cross-matching in the league.
Small forward
George
First Team: Paul George, Indiana Pacers
Second Team: Draymond Green, Golden State Warriors
Honorable Mention: Kevin Durant, Oklahoma City Thunder; Danny Green, San Antonio Spurs; Kawhi Leonard, San Antonio Spurs
Though George's shooting percentages have slipped after a fast start, he hasn't suffered the same kind of regression defensively. His 6-foot-9 height (or is it 6-10?), wingspan and quickness allow him to match up with wings of all kinds, and George is terrific in the passing lanes. If any perimeter player is going to win Defensive Player of the Year, George might eventually be it.
Draymond Green is a stunning All-Defensive choice for a few reasons. First, he's a reserve, though he's not alone there this year (foreshadowing!). More importantly, when Green came into the league, the assumption was that he'd be a useful offensive player if he could find anyone to defend. After slimming down, Green has proved to be one of the league's most versatile defenders, and if he's considered a wing (he also plays plenty as a small-ball 4), only teammate Iguodala has a better defensive RPM among this group than Green's plus-3.8 mark. When both players are on the floor, the Warriors allow just 92.6 points per 100 possessions per NBA.com/Stats, which would blow away the Pacers' league-leading 96.5 defensive rating.
Danny Green and Leonard are two more teammates with complementary skill sets. Leonard is better at defending bigger wings and stretch 4s, while Green can smother smaller players with his wingspan. Durant's defensive improvement merits an honorable mention. When locked in defensively, he's nearly impossible to beat one-on-one. According to Synergy Sports, opponents average 0.62 points per isolation play against Durant, the best mark among players who have faced at least 100 isolations.
Power forward
Duncan
First Team: Tim Duncan, San Antonio Spurs
Second Team: Taj Gibson, Chicago Bulls
Honorable Mention: Chris Bosh, Miami Heat; Serge Ibaka, Oklahoma City Thunder; Amir Johnson, Toronto Raptors
If RPM had a Defensive Player of the Year vote, it would go to Duncan. While Sanders and Garnett have rated better on a per-possession basis, Duncan's superior durability gives him more defensive value by this measure. To even have Duncan in the discussion at nearly age 38 is, of course, remarkable. He's learned to compensate for declining athleticism with superior positioning and discipline.
The other reserve All-D pick is Gibson, a possible Sixth Man Award winner. Few players are better at defending on the perimeter after switches (an area where teammate Joakim Noah also excels), and Gibson does a remarkable job of protecting the rim for a power forward. Ibaka, for all his shot-blocking prowess, lags in RPM (+2.6), and the Thunder's defensive swoon has probably ruined his chances at Defensive Player of the Year. Bosh is quietly key to a Heat defensive scheme that asks more of its big men than any in the league, while Johnson deserves the most credit among players for Toronto emerging as a top-10 defense.
Center
Hibbert
First Team: Roy Hibbert, Indiana Pacers (Defensive Player of the Year)
Second Team: Joakim Noah, Chicago Bulls
Honorable Mention: Andrew Bogut, Golden State Warriors; Marc Gasol, Memphis Grizzlies; Dwight Howard, Houston Rockets
There are four centers who merit All-Defensive and Defensive Player of the Year consideration, but my choice remains the same it has been all season: Hibbert. While Hibbert is good but not great by defensive RPM (+3.6), I think that understates his contributions to one of the best defenses in modern NBA history. Indiana's scheme is built around Hibbert's ability to protect the rim. No player who has faced more than 100 shots at the rim has allowed a lower shooting percentage than Hibbert (41.5 percent, per NBA.com/Stats). And that doesn't count the shots that Hibbert's presence deters from being taken in the first place, as the Pacers are one of the four teams that allow attempts at the rim on fewer than 30 percent of opposing shots. Hibbert's use of verticality has been imitated this season but not yet duplicated, and it's a major reason -- on top of everything else -- that Indiana ranks in the league's top 10 in keeping opponents off the foul line.
Take your pick among Bogut, Howard and Noah for the second spot. Howard (+4.9) has an elite RPM but hasn't been as effective at stopping opponents at the rim (47.8 percent). Bogut has been great by both RPM (+5.0) and opponent shooting at the rim (45.5 percent), but his limited durability knocks him to honorable mention. That leaves Noah, whose defensive RPM isn't quite as good (+3.7) but is unquestionably the most versatile defender at the center position. He excels against the pick-and-roll and also forces more steals than the other contenders. That makes Noah my second-team pick. Gasol would be in the conversation again, too, if not for the time he missed due to injury.