In order for the San Antonio Spurs to truly beef up their attack and grab LaMarcus Aldridge without having to part ways with Tim Duncan, Kawhi Leonard, and Danny Green, they need to find a way to shed a significant amount of money. The way they can do that is by moving someone like Tiago Splitter or Boris Diaw and not bring back in money in return for the deal. In order to do that, you need to get back a non-guaranteed deal of eight figures.
The Cleveland Cavaliers have one of those in Brendan Haywood. His $10.5 million for next season aren't guaranteed, which makes him a prime trade candidate this offseason. According to Mike Monroe of the San Antonio Express-News, the Cavs and Spurs are discussing a trade for Haywood's contract, which would then help the Spurs make the biggest splash of the offseason.
A deal of either Splitter ($8.5 million) or Diaw ($7.5 million) along with Patty Mills ($3.5 million) could work for Haywood, and then the Spurs could waive the center for extra cap space. If that happens and the market breaks just right for San Antonio, they could add Aldridge, retain Green, give a pay cut to Duncan, and re-sign Leonard. They'd likely have to renounce the free agent rights of Cory Joseph and Marco Belinelli. They're also waiting for a decision on Manu Ginobili and whether or not he'll retire.