I think this Tim Duncan (C) + Tiago Splitter (PF) is pivotal to San Antonio's chances of winning an NBA Title. If they can make this work, I'll become a lot more optimistic about their title chances.
They need Splitter in there alongside Duncan to give their interior defense and rebounding more of a boost. The unanswered question so far is how much will it cost them offensively.
I'd love to see San Antonio put Ginobili back in the starting lineup. I still do not think he is playing enough minutes. And now with Splitter starting alongside Duncan, Ginobili could give a more offensively challenged Spurs starting unit that offensive boost they need to make it work. If there are problems, I hope Popovich at least tries Ginobili alongside the twin towers before deciding to go back to his smaller lineup.