The Oklahoma City Thunder led the NBA in efficiency differential during the preseason with a mark of +12.5.

During the 14-15 preseason, the Golden State Warriors had the league's best mark with +11.0, which became a first indicator of their jump as title contenders.

Here's the full rankings from the 15-16 preseason:

1. Thunder: 12.5
2. Celtics: 11.6
3. Grizzlies: 11.5
4. Wizards: 10.4
5. Hornets: 10.0
6. Pistons: 7.1
7. Raptors: 5.6
8. Pacers: 4.7
9. Knicks: 4.0
10. Suns: 3.9
11. Nuggets: 3.5
12. Kings: 3.3
13. Magic: 2.8
14. Blazers: 1.8
15. Jazz: 0.4
16. Heat: 0.0
17. Hawks: -0.7
18. Rockets: -0.7
19. Nets: -1.0
20. Warriors: -1.3
21. Spurs: -1.9
22. Lakers: -2.1
23. Bucks: -3.4
24. Bulls: -3.6
25. Pelicans: -3.6
26. Clippers: -4.2
27. Cavaliers: -6.5
28. 76ers: -8.6
29. Mavericks: -10.7
30. Wolves: -11.0