Coach Chan Gailey said Johnson is officially listed as probable after getting the day off Thursday to rest a sore groin that has been bothering him the past month.
Cornerback Terrence McGee won't play against Oakland because of a hamstring injury sustained in Buffalo's season-opening win at Kansas City. McGee is expected to be out for at least a couple more weeks.
Linebacker Arthur Moats (knee) is probable, but defensive lineman Torell Troup (back) is doubtful.
For a complete breakdown on all the latest injuries throughout the league, go to NFL.com's Injury Report.
The Associated Press contributed to this report.