Mayer (personal) remained away from the Raiders on Wednesday and doesn't have a timeline to return, Levi Edwards of the Raiders' official site reports.
Mayer was added to the injury report last Thursday and ended up missing Sunday's win over the Browns. Harrison Bryant took over most of Mayer's snaps, with rookie tight end Brock Bowers essentially handling the same role he had Weeks 1 through 3. A similar plan will likely be in place again if Mayer isn't back with the team before Sunday's game in Denver.