Waller (knee/back) is listed as doubtful for Sunday's game against the Broncos after being listed as a non-participant at practice this past week, Rachel Gossen of the Raiders' official site reports.
Meanwhile, Foster Moreau (abdomen/thigh) doesn't carry a Week 16 injury designation, which sets the stage for him to continue to head the Raiders' tight end corps versus Denver, assuming Waller is unavailable. Given his doubtful designation, Waller is trending toward inactive status, though Paul Gutierrez of ESPN.com relayed Friday that interim coach Rich Bisaccia left a bit of an open window open for the tight end to make an appearance this weekend. "It's been tedious progress. I'm not confident but I always want to leave it up to [Waller], to some degree," Bisaccia said. "If he feels like he runs a little bit better, maybe tomorrow afternoon's workout, if he has a chance on Sunday to go, then we'll certainly let him go."