HANG TIME NEW JERSEY – Points, rebounds and assists are nice, but plus-minus is the most important stat in basketball.
Teams win games by outscoring their opponent, and plus-minus reflects how much a team has done that in a player’s minutes on the floor. If a player isn’t scoring, he can help his teammates score and also prevent the opponent from doing so.
But in basketball, with nine other guys on the floor affecting what each player does, plus-minus always needs context, and lots of it. Who is a guy playing his minutes with? Who is he not playing his minutes with?
Furthermore, sample size is important. Single-game plus-minus can help tell a story about key sequences or the impact of a player or two on a particular night. But if you really want to get a good idea of how a team performs when a player or group of players is on the floor, you’ve got to look at a large chunk of games.
At this point in the season, we can get a pretty good idea of where teams are strong and weak. Through Thursday, 224 players have logged at least 500 minutes for one team this season.
On Wednesday, we looked at the players with the biggest on-off court differential in regard to their team’s offensive efficiency. Today, we look at the defensive end of the floor.
Measuring the difference in a team’s offensive efficiency (points scored per 100 possessions) when a player is on the floor vs. when he’s off the floor, here are the league’s five biggest difference makers, as well as a pair at the bottom of the list.
For all of them, the discrepancy between their team’s defensive numbers with them on and off the floor is as much about the guys replacing them as it is about what they’re doing themselves.
1. Kevin Garnett, Celtics
Because the Celtics use a unique substitution pattern with KG, you can get a pretty clear idea of the impact he makes. No other Celtics regular has played more 63 percent of his minutes with Garnett.
You probably figured Garnett would be at or near the top of this list, but 14.4 points per 100 possessions? That’s an amazing number, and it’s an indictment on Brandon Bass (382 minutes with Garnett off the floor), Jared Sullinger (331) and Chris Wilcox (297) … and Paul Pierce (391) and Rajon Rondo (432).
It’s also an endorsement of both former Celtics center Greg Stiemsma and guard Avery Bradley, because the Celtics’ defense only fell off 0.5 points per 100 possessions when Garnett stepped off the floor last season.
Bradley’s return (he made his 2012-13 debut on Wednesday) offers some hope, but interior defense will continue to be an issue whenever Garnett rests. (more…)