From the video

Video: Ranking Every Week 1 Running Back as a Sit or Start
Ty Johnson hasn't practiced in weeks like since the beginning of August. And as of like September 2nd or 3rd, he still was not practicing. This is obviously a relatively serious lower body injury.
Mentioned at 14:56 – 25:24Captured by STACKED 6 hr after posting

STACKED’s take

Negative signalInjury

Serious lower-body injury keeps him sidelined, boosting James Cook's role

Ty Johnson has not practiced since early August due to a serious lower-body injury. His continued absence impacts the Bills' third-down backfield role and may lead to increased reception opportunities for James Cook, who could see four to five catches per game while Johnson is sidelined.

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