Earlier today, SB Nation's Mike Prada posted a great breakdown of Tim Duncan's impact for the Spurs. He dives into the stats, and uses some excellent GIFs to illustrate his points. Here's an important part of his post:
The last several weeks prove Duncan's importance. With Duncan healthy and playing his supplementary role, the Spurs started 36-6 and were on pace for the best point differential of all time, a full two points more per 100 possessions than the Warriors'. Life was even better in the minutes Duncan played: San Antonio outscored opponents by 17 points per 100 possessions, and no other key rotation player impacted the Spurs' historically great defense as much.
But in the 10 games since Duncan suffered a knee injury (he returned Wednesday against Orlando), the Spurs have only been very good. They were soundly defeated in both tests against elite opposition (Warriors, Cavaliers) and their point differential is nearly seven points worse than the Warriors' over that same time frame.
Let's not cry poor here, but Duncan still matters. Even now, he may be the difference between a champion and a very good team.
I encourage you to check out the piece, as the things he points out in the video are very instructive. You'll come away with a greater appreciation for what Duncan does for San Antonio.