A network-accessible computer comprises a network-communications interface configured to receive player-position data via a computer network. The player-position data indicates a multi-dimensional position for each of a plurality of players participating in a sporting event. The network-accessible computer further comprises a logic machine configured to derive auxiliary information from at least the player-position data, the auxiliary information not included in the player-position data and indicating specific attributes for one or more of the plurality of players during a period of game activity in the sporting event. The logic machine packages the auxiliary information with the player-position data into a client-readable data package usable by a client computing device to construct a user interface visualizing at least the player-position data and auxiliary information. The logic machine sends the client-readable data package to the client computing device via the network-communications interface.