The Oakland Athletics moved their Triple-A minor league affiliate to Nashville on Thursday. The A's and the Pacific Coast League's Nashville Sounds announced Thursday they have agreed to terms on a four-year player development contract that runs through the 2018 season. The A's had been partnered with the PCL's Sacramento River Cats since 2000, and the proximity between the two teams made it convenient when a player was promoted or sent down - or needed an injury rehab assignment. The River Cats announced Thursday they'd reached a deal to become the Triple-A affiliate for the San Francisco Giants.