A plastic conveyor belt module with embedded spherical rollers retained in the module and a belt constructed of such modules. The module includes a module body forming a cavity, a spherical roller in the cavity, and a retainer retained in the cavity to hold the spherical roller rotatably in place. A salient portion of the roller extends outward from the cavity through the retainer past an outer surface of the module. The retainer is attached to the module body by ultrasonic welding, epoxy- or solvent-bonding, spin welding, electromagnetic welding, staking, screwing, or locking.