The Grizz were better built and trained to win against the Spurs than the Spurs were to win against the Grizz.
The Spurs were built to do well in the regular season, and in the playoffs you could see Pop trying to patch in the old style inside out game and it didn't work. Ginobili's injury had a role, but all in all the Spurs are no exception to the rule that you dance with the one that brought you, and the inside out game did not bring the Spurs to the playoffs. Tim was not relied upon during the season to win games. Tiago was not relied upon to do anything. Suddenly we start relying on them as if Tim is a secret weapon.
I really do not think there was anything this team could have done with the players they had, other than play Tiago more, to get them to the ring. They were, at best, a WCF team but no way they get out of it.
I have thoroughly enjoyed watching Tim play since he was drafted and even in college. The problem with greats like Tim is that we see them in their waning years and those who don't really know start questioning just how great they were to begin with. For that reason, I hope Tim does his retirement tour next year and enjoys his health, his kids and his wife wherever he chooses to live. He's a class act just like Dave and deserves no less.
I hope Kobe dies in a grease fire. 
j/k