Palmer (foot) was a non-participant in Thursday's practice.
Palmer has been a spectator for both of the Chargers' first two Week 18 practices, so he'll likely need to take part in Friday's session in some fashion in order to avoid a designation for Sunday's regular-season finale in Las Vegas. If Palmer is sidelined for Week 18, DJ Chark and Derius Davis could both be in store for expanded roles at receiver.