For the most part Michigan played pretty solid in coverage against MSU, but also had some significant busts that lead to big gains for the Spartans. There have been some questions about a few of the ways that Michigan has worked in coverage, and I'll briefly discuss how Michigan plays man coverage to help clear that up as well. At the end of the day, what you see from this exercise though, is that you can be very good most of the day, but if just a few mistakes get exploited, the opposing team can put up points.
People have been wondering about if Michigan is doing this right. Namely, the common complaint is not turning back and looking for the ball. In man coverage, once you flip your hips, you have two basic techniques you will play: in-phase (in-sync, in-step, in-line, even) and trail. In-phase means that you have your hip on the front side of their hip and your shoulder on the front side of their shoulder, and you're using your body to gradually deflect them in the direction you want to push them. Trail means pretty much anything else.
When you are in-phase, you can feel where the WR is and feel where he's breaking. You are in contact with him with your body and he can't get around you without going through you, so you don't need to watch him. Otherwise, turning and looking for the ball is only slowing you down or putting you out of position as the receiver continues on his route. So when you are in a trail technique, your focus remains on the receiver and you try to go up and through the face, between the arms, and rake/rip down, only turning looking when you essentially catch back up, or in other terms, get in-phase again.
In this case, the LB never recovers to get back in phase. Instead, he is in a trail position. So what he's doing is reading the receiver's eyes. When he begins looking for the ball and he gets his hands up to catch the ball, Morgan goes up to make a play if the ball is put in a good spot.
So the set up here is that Michigan is in a two high coverage, either cover 2 or cover 4, my guess is cover 2. In this case, Lewis has help over the top and to the inside. It's important to note that it is over the top and inside. Lewis lines up and plays a hang coverage, which is an outside technique that is played so that both the WR and QB are in the same line of vision.
Where Lewis gets beat is in his technique. He gets too far off with his hang coverage and loses sight of the WR and only sees the WR in his peripheral. He doesn't properly maintain vertical and horizontal position maintenance. When the QB pump fakes the slant route, Lewis breaks down, but he's taking a path that breaks over top of the WR to beat his front shoulder across. You can't do that if you don't know where the WR is. Because what it has done here is that he essentially jumps to the same area Gordon is covering. You only take this path when you know the WR is running a slant and you see the ball in flight.
In a hang coverage (an outside technique), you route progression is: Out, Flag, Corner, Go, and comeback. Your objective is to maintain proper position (and cut off seam), drive to the reception area on short and medium outside routes, and trail and strip on and secondary responsibilities (inside routes).
Let's assume for a minute that this is a post route, because as far as Lewis knows this is a post. There is no point in being revisionist about it because it is clear that this defense needs to respect the slant. So Lewis is playing an outside technique against an inside route with help over the top and inside. What that means is that when he does drive on the slant that his aiming point is through the WR's body (which will lead him to the WR's back shoulder). This is called a trail and strip technique. He is supposed to be getting on the backside shoulder and getting his hand underneath and in the catching zone, ripping through the ball when the ball arrives.
What this also does is put Lewis in position to defend the slant and go. If he gets in proper position, then the WR then needs to fight through his body to get back outside and upfield. The WR can't continue to gain width after his fake on the slant. He's stuck only able to carry the seam up, where you have help from the safety.
Now, in my opinion this isn't on Gordon. Yes, it would be great if Gordon could get over the top and make a play here, but he doesn't. But he needs to respect the slant too. He has over the top and inside help. Because Lewis doesn't get good position, the WR can gain width, and that doesn't allow the cover 2 safety to get there.
This one is fairly simple, as you go into your drop you find what is in front of you and you understand where the first down marker is. The key here is that there is absolutely no underneath threat. What that means is that you can gain distance all the way to the first down marker. Stopping at 8 yards just leaves a window open between the second and third levels. That's what happened here. Morgan is covering grass too short in his zone. His zone extends to the first down marker, and his heals should be on the first down line. When he does break on the ball, he break horizontally rather than gaining any depth by retreating on a diagonal. That's the difference in this being a complition and an INT.
This is pretty good coverage, but it's not perfect. The key here, to the WR's credit, is that he gets a good release off the line. He doesn't lose a lot of the gap between him and the sideline. What this does is it allows him to fade and continue to gain width on his route and gives room for the pass to drop in. What gaining width does is make it so Countess can't ever get in-phase. Despite being even with the WR, he never gets proper body position.
Where he loses is on his rotation. He rotates very cleanly and gets a good run, but he takes a path that is much deeper than it needs to be. If he continues on his initial path his body takes him into the receiver. At that point he will have successfully cut off the WR, in which case he can get back in-phase and turn and locate the ball. It also drastically decreases the window, forcing the throw to go over the top to the outside. On top of that, it allows the CB to carry the WR into the sideline, making the window even smaller now. This all stems from his rotation as the WR gets a clean release. Countess needs to take a better path here, otherwise he gets stuck in trail technique (which he played well, but trail is never as good as in-phase) and will find it difficult to make a play on the ball.
So here are different players at different positions using different techniques, and they continue to need to be cleaned up. You see progress (Morgan carrying that seam wouldn't have happened earlier in the year) and you see more consistency, but one or two busts will kill you. They take you out of position and they open up windows and give the offense a chance to be something other than perfect. Now, these windows are often smaller than they were earlier in the season, but they can be much, much smaller. These are things Michigan will continue to work and improve on. These are small technique issues that need to be cleaned up for Michigan's pass defense to take the next step.