In one aspect, a scrubber brush assembly is provided. The scrubber brush assembly includes a scrubber brush including exterior molded surfaces and a mounting passage having interior molded surfaces, the interior molded surfaces having molded foam, raised rotation-restraining features, and a mandrel including recesses directly coupled to the molded foam, raised rotation-restraining features of the scrubber brush to prevent slippage. Scrubber brushes and methods of assembly are provided, as are numerous other aspects.