A mooring system comprising a submerged buoy releasably connected to a vessel adjacent its keel by a structural connector. The structural connector consists of a cylindrical sleeve coaxially movable with respect to a cylindrical housing by circumferential actuators. The lower ends of the connector sleeve and connector housing capture a number of collet segments circumpositioned therebetween that radially pivot in and out as the connector sleeve is moved axially within the connector housing. The lower ends of the collet segments extend downward to a connector hub on the buoy and releasably engage a groove therein, dogging the bearing hub against the vessel. A combined bearing assembly that supports both axial and radial loading revolvably connects the buoy to a moored chain table.