For the first time since LeBron James was named MVP of both the 2011-12 regular season and the NBA Finals -- earning his first championship in the process -- the question of the league's best player is legitimately up for debate.
Chalk that up in part to James' numbers being down in a season where he's been accused of coasting, and at least in equal measure to Kevin Durant's leap forward with teammate Russell Westbrook out of the lineup.
Aside from pivotal moments in the narrative, including Sunday's All-Star Game (when Durant outplayed James but struggled in the fourth quarter of a Western Conference loss) and tonight's second and final head-to-head meeting of the regular season in Oklahoma City, how will we determine when Durant has passed James? And, given that it hasn't happened yet, when might we expect Durant to close the gap? Let's take a look.
Who's better right now?
From a statistical standpoint, it's no contest. No matter what advanced box-score metric you prefer, Durant leads James and everyone else in the NBA. He's tops in PER (31.0 to James' 29.4), Win Shares (13.7 to 10.7) and my WARP metric (16.2 to 13.6).
But there's a difference between being the best player in a given season and being the best player in the league. There's too much variability in results from season to season, which is why statistical projections like my SCHOENE system improve accuracy by including performances from the previous three seasons.
The most recent example of the season's best player not being the league's best player involves James during his first year with the Miami Heat. As he adapted to sharing the ball with Dwyane Wade, James saw his numbers take a hit, and Dwight Howard was nearly his equal in advanced stats. Voters handed the MVP to Derrick Rose, but James was still the NBA's top star, as he proved the following season.
It's unclear how long Durant would have to outplay James to supplant him atop the league, but it is certainly longer than one full season, let alone a partial one. From a statistical standpoint, looking at the baseline for SCHOENE's projections for both players reinforces this. Incorporating the past three seasons, with a heavier weight on 2013-14, James still rates 4.4 percent better than Durant. Durant has been the better player so far, but looking ahead to the playoffs and beyond, expect James to have the upper hand.
Projecting forward
Besides coasting, the other possible culprit in James' decline this season is nothing more sinister than age. He turned 29 in December, putting him at the back end of the five-year period (ages 25 to 29) when NBA players generally peak. After all, his biggest drops have come in the categories tied most directly to athleticism -- block rate (0.7 percent, down more than 60 percent), steal rate (1.9 percent, his lowest since 2006-07) and rebound rate (11.9 percent, down nearly 10 percent).
As they age, all players compensate for declining athleticism by improving their skills and understanding of the game, and James has proven uniquely capable of doing so. That's why in a down season, he's still a more efficient scorer than ever in his career.
There's some indication that superior skill allows the league's top superstars to hold off aging more than their mortal peers. On average, the 15 players with at least 200 career WARP -- all of them either Hall of Famers or certain to be elected when eligible -- posted their best per-minute statistics between ages 28 and 29, slightly older than the average of all players. (Oddly, James, whose best statistical season was 2008-09 in Cleveland at age 24, had one of the earliest peaks among this group.) Nonetheless, Father Time remains undefeated, and eventually it will cause James to gently decline.
Meanwhile, Durant is taking his game to new heights. Still just 25, he's only beginning his prime. To see where his ascent might meet James' descent, I used SCHOENE to project the remainder of their careers, assuming both played through age 38 -- another nine seasons for James, and a full 13 for Durant. Here's how their player win percentages (the per-minute component of WARP, equivalent to PER) project going forward graphically:
The lines (red=James, blue=Durant) reflect performance through this season, while the dashes show projected future years. In the projections, James bounces back to hold the top spot through next season before Durant surpasses him for good in 2015-16, when James will be 31 and Durant 27.
Barring injury, Durant will eventually catch James. Their difference in age makes that an inevitability, because it's larger than the difference in their established performance. There's far too much noise in the projections to know whether that might happen next season or not until several more down the line.
And perhaps it's better that way. While Durant tried to downplay any competition with James at All-Star Weekend, as long as the question of the league's best player is up in the air, both Durant and James will be motivated to deliver their best possible performances. Tonight's results will make a statement that lingers beyond the outcome of the game.