An injection molding machine includes a base and an injection unit mounted to the base, and a first platen for holding a first mold section and a second platen for holding a second mold section. The first and second platens are supported by the base, and are movable along a machine axis between mold-open and mold-closed positions. At least a first tie bar engagement apparatus is associated with a first tie bar and includes a first bore in the first platen for receiving the respective tie bar therethrough at least when the platens are in the mold-closed position; and a first roller mounted to the first platen proximate the first bore. The first roller is rotatable about a first roller axis that is oriented horizontally and perpendicular to the machine axis.