We move on to the defensive tackles as I work through the positions and players on the Raiders draft radar. Along with the player, I include the round in which the Raiders would be likely to take the player should he be available with their pick in that round.

Perhaps no position on the Raiders is in more need of an upgrade than defensive tackle. The team lost three starters from last season - Richard Seymour, Tommy Kelly, and Desmond Bryant. They replaced them with two free agents on one-year deals - Vance Walker and Pat Sims. Walker has never been a starter and Sims is a rotational player. Great teams are built in the trenches. That building starts Thursday.

Here are those defensive tackles who show up on the Raiders draft radar:

Star Lotulelei, Utah - Round 1

If the Raiders stay with the third overall pick, Star is the odds on favorite to be the pick. He fills a need position for the Raiders at nose tackle while being versatile enough to move around the line in different schemes. He was the most dominant defensive tackle following the college football season and that doesn't change. There was that little scare with his heart at the combine but that turned out to be a false alarm. Once he was cleared of that, he retained his spot as a top five caliber prospect. This 6-3, 310 pound brute is violent and powerful, consistently pushing his blocker into the offensive backfield. He has improved his numbers each of his three seasons at Utah, reaching 10 tackles for loss, 5 sacks, 4 batted balls, 3 forced fumbles, an 4 fumble recoveries as a senior. Even with his dominance, scouts still see plenty of upside to him.

Sharrif Floyd, Florida - Round 1

There are those who say Floyd is a top three pick and those who say he is all hype. Defensive tackles don't typically put up a lot of stats so it can be difficult to know for sure just how talented he is. But make no mistake, he is talented. He isn't as versatile as Lotulelei and he also didn't have a lot of production (4.5 total sacks in his college career). The 6-3, 295 pounder is seen as a fit for a 4-3 defensive tackle or perhaps 3-4 defensive end. The word as of now is if the Raiders don't take him, he could fall a bit which means if the Raiders traded down, they might still have a chance to draft him. His value is in his potential and he is seen as a guy who has only begun to tap into it. One of the best things about Floyd is his incredible story which is very much like that of Baltimore Ravens' offensive tackle Michael Oher whose story was told in the film "The Blind Side".

Brandon Williams, Missouri Southern - Round 3

They don't get much bigger than this man. And at 6-2, 341 pounds, he is surprisingly athletic as well. The logical place for him would be nose tackle but he could also play 3-tech defensive tackle is asked to do so. He dominated his level of competition and after three straight seasons of over 16 tackles for loss and 8 sacks, he was invited to the Senior Bowl where he showed he was not small school fluke. He was an every down player at Missouri Southern, which is rare for a player of his size. He shows a passion for the game that Reggie McKenzie loves.

Jordan Hill, Penn State - Round 4

Current Raiders defensive end, Jack Crawford shared a defensive line with Jordan Hill for his first three seasons at Penn State. Crawford has the strong character traits the Raiders look for in their prospects and Hill does as well. He is also smart, tough, and durable. The 6-2, 294 pounder fits best at the 3-tech defensive tackle position. He has improved his numbers each season as a Nittany Lion including having 16.5 tackles for loss and 8 sacks combined over the past two seasons. He was a situational player for the Nittany Lions and most see him in a similar role in the pros.

Mike Purcell, Wyoming - Round 7

This is the kind of guy a team has to take a chance on. He led all Mountain West defensive lineman with nearly 7 tackles per game which is impressive for any position - it's remarkable for a defensive tackle. All he did was record five or more tackles in 11 of 12 games last season, finish with 83 tackles including 8.0 tackles for loss to earn first team All Mountain West honors. He was invited to the NFLPA Bowl and very likely punched his ticket as a draft pick. He is the type of player who will grind and fight his way onto a roster and would be a valuable addition as depth at defensive tackle.

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