Mark J. Terrill/Associated Press

The NFL Scouting Combine is just over one week away, and with it, the draft will see a major shakeup. It's time for one last look at my Top 300 big board before Indianapolis.

NFL teams have a system that I've followed in my work, and it goes as follows: In the fall, I watch three games of any player in my database and either flag him as "undraftable" or assign a talent grade. I'll then revisit these players in the winter (after the NFL season ends) and update my notes and grades on the players while also including any juniors who declared for the draft. The next step in the process is to update players after the NFL Scouting Combine.

With the first big update of the year out of the way, here's a look at the Top 300 by position.

Jeff Gross/Getty Images

You won't see anyone comparing this class to 2011 or 2014 in terms of overall talent, but the 2015 draft class is very strong at some positions. Running back, wide receiver, offensive tackle, defensive tackle and edge-rusher are all quality positions with top-end talent and depth.

The 2015 class is the "Year of the Pass-Rusher," though, and my top 10 is anchored by four defensive linemen. Of my top 15 overall, only five play on offense. It's a surprisingly great year for defenders, which is good news for fans in Dallas and Chicago.

Ronald Martinez/Getty Images

If your favorite team needs a quarterback and is picking outside the top six in the draft, you might want to start looking at Christian Hackenberg highlights on YouTube.

After Jameis Winston and Marcus Mariota, the 2015 draft class is the worst one I've ever seen. There is no other player who has starting-caliber tools. UCLA's Brett Hundley has some talent and athleticism, but his quarterback tools are all over the place. The rest of the class is very disappointing in terms of actual QB play.

It's Winston, Mariota or wait until next year.

Mike Zarrilli/Getty Images

The running back is back.

An early look at the 2015 draft class shows multiple running backs graded higher than last year's top-drafted back, Bishop Sankey. That starts with Todd Gurley, a legit Heisman Trophy candidate and top-15 player before tearing his ACL in mid-November. The former Bulldog could still be a first-round pick if his rehab looks good by late April.

You can pick your flavor between Tevin Coleman (Mr. Compete), Duke Johnson (Mr. Speed), Melvin Gordon (Mr. Production) and T.J. Yeldon (Mr. Power) and have a good No. 2 back in this class. These four runners should all be off the board by the mid-second round. 

The depth here is good, too. David Cobb, Ameer Abdullah, Mike Davis and Jay Ajayi all project as future starters.

Kevin C. Cox/Getty Images

The fullback position isn't as widely used in the NFL as it was 20 years ago, but teams that rely on one will be surprised by the talent available in this class.

Alabama's Jalston Fowler might be my favorite player to watch on film in the entire class. He's big, powerful, mean and can both run with the ball and block. Connor Neighbors is a wrecking ball at fullback despite not having exceptional size. 

The guy to watch here might be South Dakota State's Zach Zenner. He didn't get a combine invite, but I do like his upside.

Stacy Revere/Getty Images

The 2014 draft brought us Sammy Watkins, Mike Evans and Odell Beckham Jr. atop the class (and the same order for my pre-draft rankings). The 2015 class doesn't have any one player ready to compete with last year's top three, but there is a solid group of three studs with Day 1 talent.

Kevin White, Amari Cooper and DeVante Parker are all vying for the top spot right now, and it's a close race. White and Parker have size, length and the ability to beat defenders with their bodies, but Cooper is a silky smooth route-runner with speed. All three figure to be selected in the top 12 picks.

The depth in this class is very good, with the wild card being former Missouri and Oklahoma wide receiver Dorial Green-Beckham. He has a checkered past, though, and how early teams will want to invest in a first-round talent with seventh-round red flags remains to be seen.    

John Raoux/Associated Press

The 2015 tight end class doesn't have that one top-10 star, but this is a very good class in terms of depth and value. 

Maxx Williams is a classic late first-rounder who could be a stud in the right scheme. He's a baby Travis Kelce but is super athletic and has unlimited upside. And the class as a whole has a lot of raw talent. Blake Bell (a former quarterback) and Clive Walford (a former basketball player) have high ceilings and could easily outplay their draft stock.

Charlie Neibergall/Associated Press

Over the last five years, an average of 4.5 tackles have gone in the first round. That trend should continue in 2015, as the tackle class looks very solid yet again.

Seniors Brandon Scherff, La'el Collins, Cedric Ogbuehi (even with a torn ACL) and T.J. Clemmings carry Round 1 grades. Add in juniors Andrus Peat and Ereck Flowers and there are six tackles with legitimate claim to a first-round grade.

The depth here is very good, and that's anchored by juniors D.J. Humphries, Donovan Smith and Jeremiah Poutasi. Keep an eye on each as a potential riser as evaluators have more access to tape.

Brynn Anderson/Associated Press

Don't get your hopes up for a quick fix at offensive guard in Round 1 this year. Or Round 2. There's no Zack Martin or Joel Bitonio in this class, but remember that Brandon Linder was drafted in Round 3 and became a top starter in his rookie season.

A.J. Cann is a good run-blocker with the athleticism to improve in the pass game to get to that high level. He's talented enough to start as a rookie. The same could be said for Senior Bowl standout Laken Tomlinson, Josue Matias, Arie Kouandjio and Tre' Jackson—all are experienced, talented guards with starter upside.

Small-school star Ali Marpet—a player I hadn't heard of until December—is a legit starter inside too.

Mark J. Terrill/Associated Press

Making the transition from college center to pro center isn't easy, but it can be done well. Look at Travis Frederick or Corey Linsley as recent examples of rookies who have had a major impact on their new teams. 

There are three players in the 2015 class who qualify as potential impact centers. Cam Erving, a former tackle, Reese Dismukes and Hroniss Grasu. Each has the athleticism and intelligence to make the jump from college to the NFL without slowing down.

A sleeper prospect here is Greg Mancz. He's been impressive on film but is flying under the radar a bit currently. 

Nati Harnik/Associated Press

I've taken the liberty of naming the 2015 NFL draft the "Year of the Pass-Rusher," and if you see how many players are ranked below, you'll understand why.

An adjustment post-Senior Bowl has the class down to 25 players in my top 300 (from 32), but the overall talent is very impressive. With six players in the first round and another three (Orchard, Odighizuwa and Hunter) capable of pushing into that area, we could see nine defensive ends off the board very fast in the 2015 draft.

Two players I like a lot who may rise with more time—Preston Smith and Trey Flowers.

Mark J. Terrill/Associated Press

If I could rank players "1a" and "1b" at the top of my rankings, I'd put Leonard Williams up there with Jameis Winston. But I can't—or rather, I think that's cheating—so Williams comes in at No. 2 overall. For now. That may change.

Williams is the star of the group, but nose tackle Danny Shelton is a damn good player in his own right. Shelton's lack of "wow" plays on the highlight reels is misleading, as he does the dirty work so the rest of the defense can make plays. Add in Malcom Brown, Eddie Goldman and Carl Davis, and this defensive tackle class is five deep in Round 1.

Rick Scuteri/Associated Press

With just one player ranked in the first round, the outside linebacker rankings look light, but consider that many of the defensive ends would be linebackers in a 3-4 defense and this class fills out a lot.

Shaq Thompson could have his position listed as "Athlete," as he's played running back, safety and linebacker, but sees his pro position on the outside. He's definitely talented enough but will have to adjust to the speed of the NFL, which will stress his instincts. 

Vic Beasley is a nice edge-rusher, but it will be a shock if he actually weighed 235 pounds in-season. Kwon Alexander and Paul Dawson are both starting-quality linebackers who have just one or two holes in their games that keep them out of the first round.

Kevin C. Cox/Getty Images

Every NFL fan wants the next Luke Kuechly or C.J. Mosley, but unfortunately, there's no one of that level available in the 2015 class. But don't be too discouraged, as the top three linebackers here are all rookie-starter material.

Benardrick McKinney could play any linebacker spot in a 4-3 defense and offers unreal athleticism combined with instincts and production at the "Mike" spot. Eric Kendricks and Denzel Perryman won't meet ideal height metrics, but they both can fly to the ball and have taken over games during their careers. Perryman might be the hardest hitter in the entire draft too.

My sleeper here? Hayes Pullard. And yes, it's weird that a sleeper could come from USC, but he's being overlooked right now. 

Otto Greule Jr/Getty Images

It can't be said lightly, so here it is: There isn't a top-10 or top-15 cornerback in the 2015 draft class. Not yet, at least. 

The draft's best cornerback—Marcus Peters—was dismissed from the Washington Huskies and will have to answer questions about his character to keep his Round 1 status. After Peters, take your pick between Trae Waynes, Jalen Collins, Kevin Johnson, Alex Carter and P.J. Williams as the top corner. Each could lay claim to that ranking depending on what you (and what NFL teams) want from the position.

A few sleepers to track: JaCorey Shepherd, Jacoby Glenn and Imoan Claiborne.

Stephan Savoia/Associated Press

The best free safety in college football pulled down 14 interceptions in 2014, tying the NCAA record for single-season interceptions. Now he's headed to the NFL. 

Gerod Holliman won't be a player everyone likes, but his ability to play in coverage and attack the football in the air makes him a Round 1 talent to me. He's not a big hitter, but he'll make his money by getting the ball into his hands. 

The rest of the safety class is good, but not overwhelmingly so. Derron Smith, Durell Eskridge, Cody Prewitt and Kurtis Drummond could all be Day 2 guys and play early in their careers, but each also has a hole in his game that makes him less than a Round 1 talent. Josh Shaw, a cornerback at USC, projects best to free safety in these rankings, so keep an eye on him. 

Brynn Anderson/Associated Press

When scouting strong safeties, I'm looking for the next Sean Taylor. In the last decade, there hasn't been a player of that caliber, but he's the gold standard all others are compared to. 

Landon Collins may get that comparison from some. He's freaky athletic, wears No. 26 and could be a top-10 pick. But he's not as insanely large as Taylor was, nor is he as good when the ball is up for grabs. Collins is a very good player, but not on the iconic level. He should still go in the top 10 picks of this draft.

After Collins, this class is fortunate that Chris Hackett entered the draft. He's a solid hitter, can play both in the box or single-high and has shown very good range.