Thin at the top, deep throughout

Welcome to Scouts Inc.'s tier rankings. What are the tier rankings? They are a helpful draft resource for some NFL general managers (I know of three specifically who utilize this tool). It can help to show which portions of a draft class are deep and which are lean -- both in overall talent and at certain positions.

Tier rankings also can serve as a valuable tool for teams when considering a trade. "What's the likelihood of a player from our Tier 2 still being available if we move back X number of spots? Or is it more likely that we'll be stuck with a Tier 3 player at that point?"

These tiers are in no way set in stone. Keep in mind, it's early. We're still grinding through tape, sorting through medical and character reports as more information comes in from NFL teams. But here is the first edition of 2013 tier rankings. We begin with a comparative overview to the 2012 class.

How does this class compare to 2012?

Three of the six prospects in Tier 1 last year played offensive skill positions -- two quarterbacks (Andrew Luck and Robert Griffin III) and one running back (Trent Richardson). I also had QB Ryan Tannehill and WRs Justin Blackmon and Michael Floyd in Tiers 2 and 3, so six of 19 in the top three tiers were offensive skill players.

This year's group is quite a different story. There isn't a single offensive skill player who can be found in the top three tiers. In addition, Luck and Griffin had grades of 99 and 98, respectively. This year's top grade at this point is 97 (Luke Joeckel and Sharrif Floyd) and that's the ceiling.

This year's draft is getting little hype because of the void of first-round offensive playmakers. The reality is you don't want to be picking in the top five this year, particularly if you're in the market for a quarterback. But if you take Luck and Griffin out of the equation, there's not nearly the difference in talent level from 2012 to this year's class as most want to believe. In fact, from Tier 2 on, a case can be made in favor of 2013 having the superior talent.

Where this draft is particularly strong is along the offensive and defensive lines with four offensive tackles, two guards, five defensive tackles and three defensive ends in the top four tiers -- 14 of the top 25 rated prospects.

Day 2 is where the 2013 draft is especially strong with 82 prospects owning grades in Tiers 5-7 (compared with 66 in 2012). This is also where the offensive skill players and defensive backs should start flying off the board. Just take a look at Tiers 5, 6 and 7. They are dominated by cornerbacks (14), running backs (eight), wide receivers (eight), safeties (six) and tight ends (five).

That leaves us with the quarterbacks. This is the deepest and most jumbled group of Tier 5-7 quarterbacks that I've studied in a given year.

Keep in mind; the past three years we've seen an average of 3.3 quarterbacks selected in Round 1 compared with only 2.6 in Rounds 2 and 3 combined. We all know that quarterbacks get bumped up because of positional value, so it shouldn't surprise anyone if two or three wind up drafted in the first round.

But from a pure grade-value standpoint, there are seven quarterbacks that belong in Tiers 5-7 (Tyler Wilson, Ryan Nassib, Matt Barkley, Landry Jones, Tyler Bray, EJ Manuel, and Mike Glennon) -- and Geno Smith barely made the Tier 4 cut. And they come in all different flavors, so scheme and skill-set preference will play a big part in determining the order in which these guys are selected.

Teams in search of precision passers to fit variations of West Coast-style offenses probably will favor Wilson, Nassib and Barkley. Teams that feature more of a vertical passing attack will seek the stronger-arm prospects in Jones, Bray, Manuel and Glennon. And of the seven, Manuel is the only one with the size, mobility and experience to be considered a legitimate zone-read option threat in the NFL.

Here's my seven-tier breakdown of the top prospects, listed in order of draft grade. Non-seniors are noted with an asterisk.