The Patriots defense struggled throughout the day, most of all in a 17-point second quarter for Buffalo, but as New England's defense has done at other times this season, it held on and made the right plays at the right time to come out with the win.
As long as their offense continues to be one of the most prolific in football, they can get by with "good enough" on defense. We're used to seeing the Patriots defense perform better in December than they do in September, but this was not a step toward that goal.
It wasn't all bad, though, and ended with the Patriots making some key plays.
Namely, Devin McCourty made the two biggest plays of the game. He forced a fumble on Bills running back Fred Jackson at the one-yard line in the fourth quarter along with the game-sealing interception of quarterback Ryan Fitzpatrick in the end zone.
That final play was made possible by a rookie mistake, according to Joe Buscaglia of WGR 550 Sportsradio.
With the game on the line, [Bills wide receiver T.J. Graham] ran the route that he thought was correct in to the end zone. His route was open, in fact. The only problem? He ran the wrong route. With Ryan Fitzpatrick on point for most of the game, the spot he threw the ball to likely would have resulted in an incomplete pass at the very worst.
They won't get that kind of assistance on a regular basis. They'll have to make plays at some point, but their pass defense continues to be one of the worst in the league.
On the season, the Patriots give up a completion percentage just under 66 and a defensive passer rating just over 96. Fitzpatrick completed 67.5 percent, and finished with a 99.7 passer rating on the day. The Bills contributed five pass plays of 20 yards or more to the Patriots defense's league-leading total of 47.
And there were more than a couple of 18- and 19-yarders.
The pass rush hit its mark and put pressure on Fitzpatrick at times, but it was spotty at best, making it all too easy to find the soft spots in the defense.
Will the Patriots defense improve this season?
A lot has been made about the trade for cornerback Aqib Talib and the stability it could bring to the secondary, but without consistent pressure, the defense might still find it difficult to improve.
The Patriots had done a bit more blitzing in their contest with the Rams, and a bit more zone exchanging as well, but were burned on at least one blitz for a touchdown pass. The Patriots sacked him three times, but the pressure didn't flummox him enough to keep him out of rhythm.
Momentum swings don't begin to define what we've seen in these games. Leads of 18, 21 and 14 have turned into losses by one, 28 and 24 in the previous three meetings. This time, a 14-point lead nearly dissolved in the waning moments. Never a dull moment when the Patriots and the Bills square off.
"It was a good victory," said Deion Branch (per The Boston Globe), "but none of us feel good."
Better to win ugly than lose ugly.
Erik Frenz is the AFC East lead blogger for Bleacher Report. Be sure to follow Erik on Twitter and "like" the AFC East blog on Facebook to keep up with all the updates. Unless specified otherwise, all quotes are obtained firsthand.