cat-and-mouse game
1. A situation characterized by two parties engaged in a constant back-and-forth routine in which the advantage alternates between them. It's been a real cat-and-mouse game between these two teams—we won't be sure of the victory until the very last moment!
2. A situation characterized by two parties engaged in a constant back-and-forth routine in which one party attempts to gain tactical advantage over or draw out of hiding the other, often only to be thwarted or eluded. Police have been playing a cat-and-mouse game with drug dealers in this area for years now.