Knox will miss Wednesday's opening training camp practice due to a hamstring issue, Alec White of the Bills' official site reports.
On Wednesday, coach Sean McDermott didn't provide a timetable for the tight end's return to the field, with the team taking it "one day at a time" with injured players such as Knox. The 2019 third-rounder was placed on the active/non-football injury list by the Bills on Tuesday, but he can be activated at any time, once he's ready to resume practice.