Williams is believed to have suffered a serious right knee injury in Sunday's 32-23 loss to Vegas, Ian Rapoport of NFL Network reports.
An upcoming MRI on Williams' knee Monday should reveal more details regarding his injury, but the Broncos fear that he could be facing a lengthy absence. Melvin Gordon and Mike Boone would both be in line for additional touches in Williams' absence, with Gordon likely to take on the lead role in Denver's backfield. Williams needed crutches to leave the locker room after Sunday's loss.