The defense continues to make strides under new defensive coordinator Mike Pettine, and while the offense has its moments, most of those moments have not come with Kevin Kolb at quarterback.
With this being the all-important dress rehearsal for the regular season, we'll be watching everything closely, but these are the most important factors and players to keep an eye on Saturday night.
If head coach Doug Marrone hosted a TV show, it would most certainly not be called Fun With Flags.
"I get very upset; the players know I get very upset, with more of the unforced errors," Marrone said. "Meaning that, not trying to make a play through a ball, but jumping offside and things like that. Those are things you can truly control and I think that’s where I would use the word frustration."
Despite a string of losing seasons, the Bills haven't been so bad about penalties recently. They ranked 11th-worst in penalties last year but were in the bottom 10 for penalties for two years prior to that.
Committing a lot of penalties isn't a sure ticket to missing the playoffs, but staying away from penalties—especially in key situations like in the red zone and on third down—can be the difference between winning and losing games.
For purposes of the preseason, though, penalties are one of the surest ways to get your number written down on the coach's note card. For players who are competing for roster spots, one penalty can make a big difference.
Alex Carrington's role in the defense
Alex Carrington was most recently named the most consistent player in Bills training camp, and Doug Marrone showered him with some kind praise.
The Bills have shown a mix of 4-3 and 3-4 looks this preseason already, and Carrington has been a part of both packages. With the starters getting a significant amount of playing time against the Redskins, Carrington's role—both his alignment and his workload—will bear watching.
He has been used in a rotation at defensive tackle when the Bills line up with four-man fronts, but if the Bills are shifting toward more of a 3-4-base look, Carrington will play an important role. He was drafted in 2010 as part of their shift toward a 3-4 defense at the time and is poised to be one of the starting defensive ends in that scheme.
He hasn't made a big impact on the stat sheet, with just four combined sacks and 32 combined pressures on 477 snaps as a pass-rusher, and 1,061 snaps overall. He has spent the offseason working on his pad level, according to Dan Goldman of the Daily Messenger, to get better at getting leverage against the offensive linemen and ultimately winning one-on-one matchups in the trench.
Improved play from Carrington could be a crucial piece in the Bills' defensive progression.
Aaron Williams' continued emergence
The Bills have been without free safety Jairus Byrd since the start of training camp during a holdout over the franchise tag. He has signed the tender but likely will not play in the game against the Redskins.
The focus, then, will still be on the play of strong safety Aaron Williams, who has really stepped up in the process of moving to the back end of the secondary. He was drafted as a cornerback out of Texas and played there his first two years with the Bills, but his development didn't go quite as planned.
At this point, it doesn't matter whether his move was a result of his poor play at cornerback, the Bills' uncertainty at the strong safety position after the departure of George Wilson, or simply Williams being deemed a better fit at safety at 6'0" and 205 pounds with a profile as a big hitter and a solid run defender.
It's not likely that Williams will be tested on his deep coverage—the Redskins' three quarterbacks (Kirk Cousins, Rex Grossman and Pat White) have combined to attempt just six passes traveling 20 yards or more through the air—but that almost poses a bigger test. Williams will be tested on his patience and discipline when roaming the back end, and if he starts to cheat closer to the line of scrimmage, the Redskins may take a shot.
Facing off against a team that ranked third in the NFL in rush attempts in 2012 should also be a good test for Williams' run defense.
This game will offer a solid look at just how far along Williams has come in every key area of his development as a safety.
Erik Frenz is also a Patriots/AFC East writer for Boston.com. Unless otherwise noted, all quotes obtained firsthand or via team news releases.