When it comes to defense, the Indiana Pacers have been outliers this season. Plotting the NBA's defensive ratings so far requires stretching the axis to include the Pacers, who have allowed just 93.5 points per 100 possessions in a league in which the average team has allowed 105.9.

Only one other team, the San Antonio Spurs (98.8), allows opponents less than a point per possession, and the difference between Indiana and the third-place Chicago Bulls (100.9) is larger than the gap between the Bulls and the team ranked 23rd (New Orleans Pelicans, 108.1).

As early as it is, such dominance requires us to consider whether the 16-1 Pacers might have the best defense in NBA history -- and how they've gotten here.