A collapsible ball game practice device is comprised of a plurality of sections, each section above a lower section being substantially collapsible into the lower section. Detent structure is provided on an upper portion of each lower section and a lower portion of each upper section to secure each upper section when raised to its raised condition. A mounting structure is provided on the bottom of the lowermost section for releasably securing the device to a basketball playing surface. Arms may be rotated to various positions. The arms may be collapsed and slid on a carrier into the uppermost section. A head structure may also be slid into the uppermost section. The sections may be collapsed such that all of them may be collapsed into the lowest section. A handle is provided in the top of the head structure for carrying the entire assembly. The collapsed device may be easily transported and/or stored. The device is particularly useful as a defensive dummy in practicing the games of basketball and volleyball.