A sizing roller screen apparatus and method for processing an ore feed that includes sized and oversize ore portions and is received at an inlet are disclosed. The apparatus includes a roller screen having a plurality of adjacent screening rollers with interstices therebetween for permitting passage of the sized ore portions, the adjacent screening rollers being rotatable to cause a first sized ore portion to pass through the interstices as while the ore feed is transported along the roller screen. The apparatus also includes a sizing roller disposed generally above an opposing one of the adjacent screening rollers, the sizing roller being rotatable to fragment at least some of the oversize ore portions passing between the sizing roller and the opposing screening roller to produce a second sized ore portion, the second sized ore portion being sized for passage between the interstices.