There was little joy for the Otters' second string on Saturday as they lost to Bonymaen by 41 points to 11.
The homesters outscored the visiting Athletic by six tries to one to progress to the next round of the cup.
Roger Sweeney and Danny Jones both picked up a brace of tries for Bonymaen, with Simon Llewellyn and Ieuan Jones grabbing one apiece.
Sweeney also converted five and added a penalty.
Wing Ian Doble grabbed a consolation try for the Athletic, while Richard Morris added two penalties.