Knox (concussion) has been ruled out for Sunday's game against the Rams, Chris Brown of the Bills' official site reports.
The 23-year-old suffered the concussion during last Sunday's win over the Dolphins and has been unable to practice this week. Knox remains in the concussion protocol and will need to fully clear it before returning to game action. Tyler Kroft is without a catch through two games this season but is likely to start at tight end for the Bills in Week 3.