ORCHARD PARK, N.Y -- The New England Patriots are a team led by its defense.

It's been a while since that could be said decisively in the Bill Belichick/Tom Brady Era, but that's where things currently stand after a tight 16-10 win on the road against the Buffalo Bills. The defense (and special teams) came to the rescue with a fourth-down stop from the Patriots' 3-yard line, and ultimately, a game-sealing interception on the Bills' final drive.

Now at 4-0, and with a road trip to face the winless Washington Redskins on Sunday, the Patriots are anything but a finished product. The silver lining, of course, is that they've built themselves some early-season margin for error.

Troubling trend: The passing game has looked disjointed since the second quarter of the team's Week 3 win against the Jets. After a Week 2 win against Miami, the unit had appeared to be on the cusp of building something special with receiver Antonio Brown, as Brown's ability to win one-on-one matchups and make plays on all three levels of the field brought an added dimension. Though the Bills' defense deserves plenty of credit for an exemplary performance Sunday, the Patriots' passing game over the past seven quarters has been less than impressive. Brady averaged 3.8 yards per attempt, his lowest rate in a win in his career, according to ESPN Stats & Information.

QB breakdown: Very un-Brady-like. The Patriots were off to another fast start with a 13-0 lead, and driving in the second quarter, when Brady was intercepted in the end zone by safety Micah Hyde. Those types of mistakes are not the norm for Brady, and it truly changed the complexion of the game. Brady finished 18-of-39 for 150 yards with no touchdowns and one interception.

Describe the game in two words: Uphill climb. The Patriots seemed like they were working with a long field all day.

Pivotal play: J.C. Jackson's blocked punt that Matthew Slater scooped up to score his first career touchdown was one of the biggest plays of the game. Jackson is usually covering the opposing gunner, but his rush off the right side in the first quarter reflected how the Patriots used pressure effectively on their punt unit and it paid off. It also marked the second straight season the Patriots have recorded a blocked punt return for a touchdown (Kyle Van Noy, Week 7, 2018). Prior to that, the Patriots hadn't returned a blocked punt for a touchdown since Tedy Bruschi did so in October 1996.