Many here on MHR have their opinions on who should be drafted and where. We look to stats, the combine, and workout performances to help get an idea of what value a particular player has in the draft. To most who haven't played the position at some level, Defensive line is an enigma wrapped in a riddle. Often times, Defensive linemen don't produce eye popping stats, but they effect the outcome of very play in one way or another. You need to go beyond the box score to realize what kind of an impact a D-Lineman has on the outcome of a game. Tape is going to tell the tale of the Defensive lineman far better than the Combine or pro day workouts ever will. To truly evaluate the Defensive lineman, you have to break down the tape. To properly do that, you have to know what questions to ask about a prospect and what the answers to those questions mean. After the jump, we'll go over a few of those basic questions, in this writer's opinion, to better equip you to scout a position group that is considered a mystery to many here on MHR.
The first question we need to ask about our prospect: How quick does he get off on the snap? Does he time his first step well, or is there some lag between the snap and his first step? This is all anticipation and reaction time. A good Defensive lineman is always going to watch the ball and fire off as soon as he sees it move. If they ignore the QB and watch the ball, they'll never jump off sides. If our guy has a problem getting off on the snap consistently and gets caught jumping off sides, he's probably going to have problems in other areas of his game. This should be a big red flag.
There is a fallacy when it comes to the Defensive line that bigger is better. This is not always the case. A good lineman can use technique to trump size every time. Leverage is a defensive lineman's greatest ally. This brings us to the next question we should ask when scouting defensive linemen: How low does he come off the ball? After watching Doom for all the years we've had him, we all should realize that a low center of gravity is a big asset to defensive linemen. There is more of a chance for success if our guy consistently fires off the line lower than the man who is trying to block him. This is literally a balancing act. You want your guy to fire out low, but still be able to move his man with a solid base underneath him. The level at which a Dlineman plays is very important, but it is something that can be coached if there is upside in the prospect.
Part of using leverage as a lineman is getting into the body of your man. The easiest way to accomplish this is having a guy that answers our first two questions successfully. That brings us to the next question to ask: Does our guy get into his man first consistently? If our guy is firing out of his stance on the snap of the ball lower than the guy who is trying to block him, he is already halfway there. Ultimately, you want to see your prospect get into his man and initially put his facemask into his man's chest. This initial violence is critical to everything else our prospect does on the play. If our guy gets this far, there is a good chance he will beat his man because he is in perfect position to impose his will on him. If Offensive lineman consistently get their hands on our prospect, preventing our guy from getting into their body, another red flag should pop up.
Once our guy gets into his man, we get to the next question which could be the most telling about our prospect: Does he read and react to the play well? While he is reading the play, he should be using the leverage he has established by keeping his feet moving and keeping a good base under him. If no offensive lineman has tried to block him, is his head on a swivel looking for the play, or is he blindly rushing up the field? If his man has pulled out to block, how does he react? This is screen and trap recognition. A good DT will follow the pulling guard right to the play. If he is the one being trapped, he'll turn to take on the trap block before the guard can ear-hole him. Poor Dlineman will fail to recognize the trap or screen consistently. This is something that can be coached but it should help to separate the men from the boys when evaluating.
Finally, we get to the part every guy likes: How does our guy finish or get off the block? The most basic finishing move for a DT is the simple shed or shuck. You hope your guy makes the play here, because his man is still alive as a blocker and free to block into the next level. The next basic move would be your bull rush where your guy basically does a pancake block in reverse, running over the Olineman. Some intermediate moves would be the club and the old Deacon Jones head slap. The more advanced moves are the rip and the swim move. You only want to see these moves in pass rushing situations because it requires the lineman to choose a side. If our guy chooses the wrong side on a run play, he can play himself out of position. With the rip move, our guy uses leverage to rip past his man to one side or the other, usually going underneath the Olineman's arm. The swim move is similar, but it works best against an off balance, over extended Olineman. Most guys can only do these moves to the left or the right. It is exceptional to find one that can rip or swim to either side. It's not important how our guy gets off the block, just that he does. These moves are better suited for certain body types. Taller guys have more success with the swim move, while shorter guys will generally find more success with the rip.
These are the basic things you should look for when scouting defensive linemen. It should be enough to get you started if you're in the dark about scouting the Dline. Keep in mind that you are looking for consitency more than perfection here. Depending on how well this is recieved, I will try to add to this with some more advanced stuff to look at. I am sure there are a few other old Dlinemen here, feel free to add anything I may have overlooked.