A method is provided for producing an assembly of an eccentric rod (15, 16) and a piston (20, 21) of a connecting rod of an internal combustion engine having an adjustable compression ratio. The method includes providing an eccentric rod (15, 16) having a first end (36, 37) for attachment to an eccentric lever of an eccentric adjusting device of the connecting rod and a second end (38, 39) for attachment to a piston (20, 21) that can be guided in a hydraulic chamber of the connecting rod. The method then includes arranging the second end (38, 39) of the eccentric rod (15, 16) in the piston (20, 21); introducing an injection-molding tool (47) into the piston (20, 21); and injection-molding a circumferentially closed retaining ring (43) between the piston (20, 21), the second end (38, 39) of the eccentric rod (15, 16) and the injection-molding tool (47).