NFL rosters are small enough that calling any player on the active roster "not useful" is a stretch. There's always a reason that players that have a hard time cracking the 46-player, active game day rosters around the league are on a team, and the Buffalo Bills are certainly no exception to this rule.
Still, there's also a reason that some members of 53-man rosters are routinely in street clothes on game days. With the team ideally getting healthier in key spots over their bye week, let's take a look at some of the names of players that may end up watching their teammates make their playoff push from the sidelines in sweats and jackets.
RB Phillip Tanner: Signed to the 53-man roster following injuries to Fred Jackson and C.J. Spiller, Tanner was inactive in the road win over New York, with Anthony Dixon and Bryce Brown the only healthy running backs on the active roster. It's pretty clear that the Bills want to have a fourth back on the team in the event that injuries crop up the way they did against Minnesota, but Tanner is going to have a hard time dressing even before Jackson returns to the lineup (which could conceivably happen in Week 10). Buffalo may end up looking for a younger, higher-upside option to replace Tanner, as well.
WR Mike Williams: Over the Bills' last four games, Williams' role has diminished significantly. In Weeks 3 and 4, Williams played 60.7 percent of snaps as the team's third receiver. Since then, he played 36.6 percent of snaps against Detroit, losing snaps to both Marquise Goodwin and Chris Hogan, then was inactive entirely against New England. He logged only a combined 17 snaps on offense (and 12 on special teams, mostly on the punt return unit) in wins over Minnesota and New York. When Goodwin and special teams ace Marcus Easley are healthy and return to the lineup, it's expected that Williams will once again return to healthy scratch territory.
OL Cyrus Kouandjio: Buffalo's second-round pick in April's draft has yet to suit up for a game this season. He is not ready, from a technique standpoint, to be relied upon even as a reserve - and that's saying something, given that the same can be said of fellow rookie Cyril Richardson, who has already started three games. Unless there's an injury to one of the seven players in front of him, Kouandjio's chances of seeing the active roster on a game day this season seem to be virtually nil.
LB Keith Rivers: This is a tough sell considering that Rivers has been active for each of the Bills' first eight games, and is a valuable reserve thanks to his experience, but hear me out. Rivers has clearly lost his starting job to rookie Preston Brown, who has played 148 snaps in the last two games to Rivers' eight (including just one in New York). Meanwhile, Rivers has also only participated in 15.2 percent of special teams reps this season, putting him well behind fellow reserve linebackers Ty Powell, Larry Dean, and Randell Johnson in that category. If he's dressed, Rivers may have a hard time seeing field time - but if the team is comfortable with Powell as the top reserve linebacker, then it wouldn't be shocking if Rivers started riding the healthy scratch train.
CB Ross Cockrell: A rookie fourth-round pick out of Duke, Cockrell has only suited up in one contest. That came in Week 1, when Stephon Gilmore sat out with an injury, and Cockrell did not play any defensive or special teams snaps in that contest. He has been inactive every week since, likely due to the fact that the team obviously does not feel overly comfortable using him on special teams. Much like Kouandjio, it's looking like the only chance Cockrell has at suiting up for a game in his rookie season is if someone in front of him on the depth chart is injured.