A braking mechanism for decelerating copy sheets being delivered to a stacking tray of an electrophotographic copier includes pairs of opposing feed rollers disposed at closely adjacent longitudinally spaced locations along the sheet path to the tray. The first pair of rollers are driven at a peripheral velocity equal to that of the upstream portions of the sheet transport assembly, while the second pair of rollers are driven through an overrunning clutch at a peripheral velocity equal to about one-third to one-half the velocity of the first pair of rollers. A copy sheet entering the nip of the second pair of rollers from the first pair of rollers acts as a rigid member to drive the second pair of rollers at the upstream velocity, overrunning the clutch. When the sheet emerges from the upstream nip, frictional drag slows the second pair of rollers down to the slower velocity of their drive source, causing the sheet to be delivered to the copy tray at a relatively low rate of speed to ensure even stacking.