In a single strand hot rolling mill finishing section a plurality of multi-stand prefinishing rolling units are arranged along and are selectively shiftable onto and off of a first pass line segment. A multi-stand finishing rolling unit and a multi-stand post finishing rolling unit are arranged sequentially along a second pass line segment. A switch and associated delivery guides are selectively operable to direct products from the first pass line segment to the second pass line segment either at a location upstream of said finishing rolling unit, or alternatively, at a location between the finishing rolling unit and the post finishing rolling unit. With this arrangement, final rolling in the post finishing rolling unit may be preceded with or without rolling in the finishing rolling unit and with or without rolling in one or more of the prefinishing rolling units.