Waller underwent an MRI on his knee Friday, which revealed a strained IT band, Ian Rapoport of NFL Network reports.
Waller left Thursday's win at Dallas on two occasions and eventually was ruled out of the contest, ending Week 12 with a pair of catches for 33 yards on five targets. It's unclear if the injury will result in time away from the field, but the Raiders have more than a week to prepare for their next game Sunday, Dec. 5 against Washington. Foster Moreau is the next man up at tight end for Las Vegas, while Daniel Helm also is on the active roster.