As I wrote earlier in the week, grades on players are always fluid as the information gathering process continues. With the Combine still a few weeks away, we are missing a very important ingredient for finalizing a grade, and that is verified measurables. For many of the seniors, we have verified heights, weights and arm lengths from the various All-Star games, but with the underclassmen, we have nothing. In both cases we have no verified speed, which is very important, especially with the skill-position players.

That being said, the defensive side of the ball in this draft appears to be a fairly good, but not a great class.

At the EDGE position, North Carolina State’s Bradley Chubb is perhaps the best player in the draft. Chubb has the size, speed and athleticism to play in any scheme and be a dominant player. After Chubb, there are three other EDGE players who could very well go in the first round — Harold Landry from Boston College, Arden Key from LSU and Marcus Davenport from UTSA. Davenport is raw, but he has tremendous upside. That upside might mean he goes off the board earlier than he probably should be drafted.

Other interesting EDGE players include Wake Forest’s Duke Ejiofor, Ohio State’s Sam Hubbard and Georgia’s Lorenzo Carter.

The DT class is interesting. My top player at the position is Florida’s Taven Bryan, who can play as a 3-tech in a 4-3 or a 5-tech in a 3-4. He is very active and plays a relentless game. Alabama’s Da'Ron Payne is the latest in a long line of Tide defensive linemen who are rated highly by NFL scouts.

I have Washington’s Vita Vea rated as a first-round player but not as high in the first as some people. The reasoning is that I see him as more of a run stopper than a player who can generate a strong inside pass rush. It will be interesting to see how high he goes.

A player that many have ranked much higher than I do is Michigan’s Maurice Hurst. Hurst has very good physical traits, but he plays with his head down and loses track of the ball far too often. He is not the most instinctive player.

A player that I have rated too low in the PFW Draft Guide because I just didn’t see enough of his tape is Virginia Tech’s Tim Settle. Settle is just a third-year sophomore and has two years of eligibility left. He is huge, very strong and quite athletic. I gave him a third-round grade in the Guide, but he could go in the bottom of the first or the top part of the second. He’s still very young and has great upside. Look for his ranking to be upgraded in my final rankings on our site.

At the LB position, Georgia’s Roquan Smith will easily be the first linebacker off the board and will most likely be a top-10 selection. There are mixed opinions on who is after Smith. Many really like Virginia Tech’s Tremaine Edmunds, who will measure about 6’5 – 240, which looks like ideal OLB dimensions but he played inside. You would think that with his size and length, Edmunds would be a top pass rusher but he isn't. The other thing that worries me is that he is more of a reactor than an anticipator. In the NFL, all quality linebackers have top instincts; that isn't part of Edmunds' game currently. He'll get drafted high on his traits but may not live up to expectations.

Alabama's Rashaan Evans is a great competitior and keeps improving. He'll be a very solid pro. The depth at the LB position is good, and there are plenty of the "hybrid" linebacker prototypes, headlined by South Carolina State's Darius Leonard.

Oklahoma's Ogbonnia Okoronkwo is a unique player. He played as an EDGE defender but lacks the height many teams want for an outside guy. I'm projecting him as a 'Will' linebacker who will sometimes lineup outside. That is what Arizona did last year with Haason Reddick, who has similar size. I like Okoronkwo, but I don't see him as being as talented as Reddick. He is more likely to be a second- or third-round prospect.

The S position includes the player whom I have rated as the second-best prospect in this draft, Alabama's Minkah Fitzpatrick. In my opinion, he is a better player and prospect than Jalen Ramsey was two years ago when he came out of Florida State. Like Ramsey, Fitzpatrick can play safety or corner, and be a dominant player at either position.

Florida State's Derwin James is my second-highest-ranked safety. I spent some time recently with James at the All-Star Football Challenge, and he is a very interesting and competitive person. The one thing that stuck out to me is that he said he was close to 220 pounds when the season started and was at about 205 when it ended. He wanted the extra bulk for when Florida State played Alabama because the Alabama run game is so strong. James is very athletic and has good man-cover skills. I expect that he will have a very good Combine.

After James, the best safeties are Armani Watts form Texas A&M, Marcus Allen from Penn State and DeShon Elliott from Texas. The S class isn't deep, and after the second and perhaps third round, the value drops off.

Until we get verified times on the corners, it can be tough to rank them. More than any other position, it is stopwatch driven. Iowa's Josh Jackson has outstanding tape and his ball skills are second to none, but he has to run fast to be the first or second corner off the board. Anything in the 4.4s keeps Jackson safely in the conversation among the first corner to be selected.

Ohio State's Denzel Ward is another player with great tape. The question on him going into the Combine is just how tall is he? If he measures taller than 5-feet-10, then he's fine. If he comes up shorter, some clubs will downgrade him. There are a number of clubs in the NFL who won't draft a corner shorter than 5-10.

The CB class is deep, but as is the case almost every year, if you don't draft one in the first three rounds, the chances of getting an eventual starter aren't very good. Almost every year, 10-12 corners get drafted in the first three rounds.

After Ward and Jackson, the best corners are Jaire Alexander from Louisville, Isaiah Oliver from Colorado and Mike Hughes from Central Florida.