Early on in the game the Jets had the ball and decided to gift the Bills a free bee. The key part of the play is Marshall and whether or not the pass was good. I'll leave you up to decide if the pass was a wise one.
The Jets lined up in 5 wide. The two outside WR run box out routes The two inside slot WR run 15 yard post/corner routes to the right. The other TE on the inside is running a out route as well a few yards deeper.
Meanwhile the defense is in cover two with man underneath. The Bills respecting Fitzmagic and his beard powers had a person spying on Fitz. They only rush three so there was little pressure on Fitz. Problem is no one really gets a ton of separation.
Now a cover two does have a weakness in the deep corners and right over the middle. Decker and Marshall are both covered pretty well. Marshall is beating his man deep so there is a window between the safeties and beyond the underneath DB.
The pass finds the window, but is tipped and lands in the safeties arm. With a window this small errors like that become turnovers.
You'll see a scenario like this again, but it goes to show you that just because a defense gives you a window of opportunity, sometimes it slams down in your face.
Meanwhile the Bills had no such issues exploiting a zone to start the second half. This is a bit of a mismatch for the D and on top of that Gilchrist gets completely exposed.
The Bills have two right, one is wide right and another tight to the OL. A TE on the left stays into block along with the left RB. The right one is the key man here, running a wheel route splitting the two deep routes. It's realistically a version of the clear out concept where they run routes designed to exploit a one on one matchup. It works here.
On defense the Jets play a cover 3 zone. They have 3 under with one man playing the screen and also spying the QB. Three men cover deep Gilchrist is the middle man with the CB and other safety between him., If I'm assigning blame, he gets a good portion of it for reasons you will see.
He does a good job of checking out the crossing post route in this image. Problem is the underneath route is about to get open. The Linebacker covering it gets caught trying to cover the outside. The RB sensing this jumps underneath, changing his route from a true wheel to almost a post route.
Here's the path each man takes once they see the RB make his break. Gilchrist for some reason runs to the sideline even though the man has turned upfield. The LB is now in trail, meaning that there is going to be a lane to the inside of the field due to Gilchrist's route.
And now you can see how badly Gilchirst is out of position.
At this point, it's a situation where only the turf monster will stop Wiliams from scoring. Bad play all around. Gilchrist got out of position and the Bills were able to exploit the one on one matchup.
On the plus side, the Jets did manage to score a few second half TD's. The first was to Marshall on a nicely designed pick play.
Once again the Jets have 5 wide but this time run 5 underneath routes. The deepest would be Decker from the left tight slot position who runs a 3 yard slant route. The two WR on the right run in routes, although the inside man runs more of a slant then in. The two men who make this play happens are Marshall who gets the ball and the outside WR who runs an inadvertent pick route.
Perhaps the key to this play was the defense. It's a cover two zone, but the one LB fakes a blitz then drops in coverage. Because of the delay and defensive play design, there's going to be a few players have to run a good distance to get in their zones. One of which will be key.
The key one would be the 3rd man having to run over. Because it is a slightly delayed zone, the deep safety has to cover Decker. That forces the second most outside zone to have to cover Marshall, while the outside zone is covering Tompkins as he goes across the middle. It ends up with a cluster as Marshall gets the ball underneath and gets to the outside using Thompkins as a screen.
You can see the result once Marshall gets to the outside. There was no interference on this play at all.
One negative: Marshall nearly blew the play by showing off just before he got in the end zone . Aside from that, nice play call and nice execution.
Let's go back to something. Let's see how the Jets can break down a cover two defense by exploiting the middle zone between the two defenders.
This time it's Decker to go across the middle from the tight slot. The Jets line up with 5 wide, 3 right including Decker and two left. The two to the left run a quick out from the slot and an arrow and up route. On the right Marshall runs deep right, while the other man runs a 5 yard quick stop route. Decker goes over the middle running a straight seam route.
The defense is in a true cover two. You can see the hole in the middle as the safety shades slightly to Marshall. His first priority is to stop Marshall running towards the pylon, but also has to help over the middle. The other safety should in theory also help cover Decker.
Instead the far safety goes up slightly helping out with the arrow and up route. The near safety favors Marshall. Meanwhile Decker gained separation on the LB over the middle. You can see how Decker's route will split the two deep zone coverage.
It comes down to a good pass that beats the underneath man, but does hang too long and allow the safeties to get to the pass. It's part touch part zip, and Fitz puts a good pass into Decker's hands.
That's how you beat a cover two defense. The Jets tried once with Marshall and then were much more successful the second time.