Kroft suffered a left ankle injury at Thursday's practice, Chris Brown of the Bills' official site reports.
After missing the first two games of the season while recovering from a broken right foot, Kroft looked poised to make his season debut Sunday versus Cincinnati following his full participation in practice Wednesday. While it's fortunate that Kroft's setback Thursday wasn't to his right leg, the injury nonetheless clouds his availability for Week 3. Dawson Knox would continue to act as the Bills' top pass-catching tight end if Kroft is forced to miss another contest.