Interesting to review this game. The first sack wasn't the result of anything fancy in terms of simulated pressure or replacement blitzes.
Clayborn runs a simple but effective stunt, selling his upfield pressure before looping back in for the hit. Flowers beats the guard from the 3tech spot. The coverage isn't exotic at all. KVN appears to be in man, although I suppose you could argue he's floating around, ready to blitz if needed since he steps up toward the line. Tough to say for sure without knowing the playcall.
In the secondary, Harmon creeps up toward the box, but bails back to his depth to help protect the middle of the field. On the side with three WRs (I am counting Jimmy Graham as a receiver by formation/route in this situation), the defenders do a good job communicating a banjo coverage instead of getting fooled by the trips formation like we often saw the previous season. Nice tight coverage, good pressure, synergistic defense.
I'll skip ahead to the final two incompletions. I found these interesting for a couple of reasons. Notice how aggressively the secondary lines up; this appears at first glance like cover 0, although McCourty and Harmon drop out into what looks like a version of cover 2 at the snap. Keep that in mind for when we look at the 4th and 4 on the next play, since they use a similar lineup. For all of the accolades that Rodgers gets -- and his play can look magnificent at times -- how often do you hear him described as a cerebral quarterback? I don't recall the Patriots throwing a lot of cover 0 at Manning later in his career, although that could be my memory playing tricks on me. It's a risky look for a reason.
The real magic happens up front on this play: Flowers and Butler on the inside shades of the guards (maybe heads up; I wish I had all-22 views), Hightower and Simon out at 7 tech, KVN hanging back to clog up the box, Chung reading the play to determine if he will blitz or peel off into coverage, and Butler dropping into the middle of the field to jam the RB. How often do you see a 1 tech (usually Butler fits the classic 3 tech profile, but here he's not on the outside of the guard, so he's playing the 1) drop into coverage? It's an effective way to stop the back leaking out, however, throwing off the timing so that Rodgers didn't risk the dump off since KVN was still hovering around the first down marker, ready to make a tackle.
Simon and Hightower rush hard to the outside shoulders, but notice their discipline to not overrun the pocket and give Rodgers an easy rushing lane to escape. The rush lane integrity is key to the pressure, since no one wins early in their pass rush, causing Rodgers to drift back and look for options. He can't go to the running back, since KVN picks him up, and Chung trails the TE, who was trying to run a quick route after jamming Hightower, which further delays the read from Rodgers. As the pocket caves in, Rodgers evades to the side he wants to throw to, but he doesn't get enough on the ball despite trying to set his feet and ends up one-hopping the football in front of Chung and the receiver. Nice discipline all across the defense.
4th and 4, game on the line. Once again the Patriots simulate a pseudo cover 0 look, although with the way that McCourty faked his blitz, I'm pretty sure Rodgers knew that there would be a safety over the middle of the field. Sure enough, the McCourty twins bracket the slot receiver, taking away the quick pass. The Patriots do use a 6-man blitz, however, dispensing with disguise and just letting everyone crash the line of scrimmage. The running back does a credible job stepping up and knocking KVN off his rush, but Clayborn got a great push despite the left tackle's blatant false start (slow down the video and he clearly starts his kickslide prior to the snap). Rodgers is forced to throw earlier than he wants to; again, he fails to set his feet and just tries to play hero ball, lobbing up a pass as he falls backward.
Chung and Jackson use press-man coverage without help. Jason McCourty has his twin for backup, which allows him to play off the line and prepare for a quick strike. Gilmore recognizes that he's 1 on 1, so he lines up at the 1st down marker, using a side shuffle, or a type of bail technique, instead of multiple-step backpedal. This allows him to keep a closer eye on the movement of the receiver in case he has to make a quick break on the ball and tackle the WR before the first down line. He easily runs with the receiver and he's in great position to make the play if necessary, but Rodgers badly overthrows the ball and the receiver never truly has a chance. Game over.
As I mentioned, the defensive calls seem quite aggressive against a supposedly HoF caliber QB. Flores had a lot of faith in the defense, and they rewarded him with fundamentally sound play that gave Rodgers few options, although he could have helped himself out better. No question he can do some special things while improvising, but he sure failed to deliver in crunch time in this matchup. Strange we never hear that narrative.