A player can be prevented from successively using an object that affects the outcome of a match in a network competition game executed among a plurality of clients via a network. An object is selected at the end of a match event of competition game by a client on the basis of action frequency of an object that has participated in a match event. Next, a notification about the object selected at this point is sent to a server and the object is managed in the server as an object that can not appear in a new match event. A notification about the object being managed in the server is sent to the client if a new match event is to be executed in the client. At this point, the client executes a process for selecting an object from among a plurality of objects excluding the notified object.