Bye-week grades offer mixed bag for frustrated Bills defensive line

Grading the Buffalo Bills at their bye week. We continue with the defensive line:

Mario Williams: As with the rest of the Bills' defensive line, the sack numbers haven't been there for Williams, which has been a much-discussed topic in recent weeks. Williams is tied for 41st in the NFL with 3.0 sacks this season, a disappointing statistic for a player who with a $20 million salary-cap number. Is that entirely Williams' fault? Of course not. He was on the mark when he noted to reporters about how much he was dropping back into coverage this season, and it's also true that Williams has been used more in an interior role at times this season, limiting his ability to use his length and speed to his advantage. Pro Football Focus has graded Williams as 117th among 147 edge defensive players. Grade: C.

Marcell Dareus: The expectations for Dareus soared when he signed a $100 million extension last month, including $60 million guaranteed. For the most part, he hasn't disappointed. Dareus ranks 10th among NFL defensive tackles according to Pro Football Focus and is the third-best tackle in stopping the run. He hasn't been as productive as a pass-rusher, tallying just one sack this season after posting seven through the first seven games of last season. Still, he's been a force. Grade: B-plus.

Kyle Williams: Williams is currently out with a knee injury and his status for the Bills' first game after their bye week, Nov. 8 against the Miami Dolphins, is uncertain. In his six games before his injury, Williams recorded one sack, matching his output from that same period last season. He ranks 47th among 192 NFL defensive tackles per Pro Football Focus, which is slightly disappointing given how Williams had played the past two seasons. Grade: B-minus.

Jerry Hughes: Hughes has just one sack through seven games, an extremely disappointing result for a player whom the Bills' front office worked diligently to re-sign to a five-year, $45 million contract this past offseason. Hughes had a total of 20 sacks in 2013 and 2014, tied for ninth in the NFL over that span. He's tied for 117th in sacks this season. As with Williams, the Bills have asked Hughes to do a lot more than just pin his ears back and pass rush; he needs to drop into coverage on some plays, too. Hughes ranks 25th among NFL edge defensive players per Pro Football Focus. Grade: B-minus.

Corbin Bryant: The coaching staff preferred Bryant as a fill-in starter over Stefan Charles when either Dareus was suspended or when Williams has been injured. Both players have been graded similarly by Pro Football Focus, however. Bryant ranks 105th, while Charles is 106th. It's a drop-off from either Dareus or Williams to Bryant, but there hasn't been a glaring weakness for the Bills at that spot when Bryant has been in there. Grade: B.

Stefan Charles: The Canadian product was one of the Bills' more promising young players when he saw spot duty in 2013 and was used as a rotational player in Jim Schwartz's defense last season. However, he's seen a drop in playing time this season. He's been on the field for 22 percent of defensive snaps, compared to 31 percent last season. Bryant is clearly the coaches' preferred choice when one of the starters it out. Grade: C-plus.

Alex Carrington: The Bills signed Carrington, who started the first three games of the 2013 season in Mike Pettine's defense before a season-ending injury, to a small-money contract this past offseason. He looked primed for a rotational role on the defensive line but has played in just 10 percent of snaps this season and has been a healthy scratch for four games. The Bills have instead opted to use Mario Williams (94 percent of snaps) and Hughes (91.5 percent of snaps) in nearly wire-to-wire roles. Grade: Incomplete.