A method and apparatus for bundling flexible risers uses a vertically-hanging riser support shaft extending below the turret of a turret-moored FPSO to manage the motions of the risers. The risers may transition to a catenary configuration as they exit a bottom structure at the lower end of the riser support shaft and connect to wellheads or flowlines on the seafloor. Certain embodiments are suitable for use with a disconnectable buoyant turret mooring system while other embodiments may be used with spread-moored FPSOs.