Rating the offensive tackles

Finding a franchise offensive tackle is near the top of the list for every NFL team, right after locating a starting quarterback, pass rusher and cover cornerback.

But in recent years, the top players selected early in the first round have failed to deliver. Jordan Gross, Robert Gallery and even Alex Barron have had their ups and downs. Still, nine tackle prospects were chosen in the first three rounds of last year's draft.

Adjusting to the speed of the game, complicated blocking schemes and the pressure of playing an "A" game week in and week out over a 16-game schedule makes the tackle spot one of the hardest to judge.

The mental aspect of the game and the player's learning curve is as important at this position as anywhere on the field. A missed block can lead to a turnover, or worse, a major injury to a starting quarterback or running back.

This year's crop features three possible first-round prospects. Expect to see a second run at the position mid-to-late third round.

TOP OFFENSIVE TACKLES

1. Joe Thomas, Wisconsin. Many expected this All-American to declare early for the draft last year. Those plans were scuttled after he suffered a right knee injury in the Badgers' bowl game. Fully recovered, he is expected to be a top-five pick, maybe even going in the first three selections.

A strong blocker at the point of attack, Thomas uses his hands to create a violent punch off the snap. His footwork and athleticism allow him to adjust and handle pass rushers off the edge.

He does not have really long arms (32½ inches) for his size (6-foot-8, 305 pounds), but his track-and-field background help him lock on and sustain his blocks.

His makeup and skill level make him very attractive for a team picking in the top five. The Detroit Lions and Arizona Cardinals seem likely destinations. The Cleveland Browns could be a dark horse.

2. Levi Brown, Penn State. A well-respected and decorated Big Ten lineman, Brown is seen by many as a first-round talent. Detractors see a bit of an underachiever.

When on his game, he is a force as a drive blocker and can handle outside pass rushers. But he takes off too many plays, sometimes gets high in his stance and suffers lapses in concentration (seven penalties the past two seasons).

The 6-5 Brown has good feet to get out and block downfield but needs to watch his weight (324 pounds) and conditioning. He missed a pair of games after suffering a torn meniscus in his left knee, the same knee that he sprained two years earlier, and was out of shape for several more weeks after his return. He can overextend and get sloppy with his technique when he starts to wear down.

He has the skill level to become similar to young All-Pro tackle Jamaal Brown. He's likely to go in the 20-to-32 range of the first round, but he could get over-drafted (top 10) by a team that feels they can get the most out of his ability.

3. Tony Ugoh, Arkansas. The All-American came into his own as a senior, playing 14 games and allowing just one sack.

Ugoh, who also competed in track until this past season, has bulked up and toughened up over the past year (6-6, 301 pounds). His footwork has improved, but he will get too shallow off the snap at times when facing quicker edge rushers.

He has long arms and his initial punch improved once he learned to keep his hands up and use them quicker off the snap. That said, he needs to increase his lower body strength.

Ugoh could be a bit of a risky pick, but a strong showing at the combine could make him a possible mid-to-late first-round selection.

4. Joe Staley, Central Michigan. The most athletically gifted blocker available, Staley could run in the 4.70 range at or above 300 pounds, do 30 reps of 225 pounds and jump 32 to 33 inches vertically.

He has the ability to get good depth off the snap to combat edge rushers, but he also shows the balance and footwork to stay in front of most bull rushers.

Staley (6-5, 300 pounds) is still learning to play as a full-sized lineman, but his maturity should also come with increased upper-body strength.

He has the makeup and skill level to develop into an above-average talent at left tackle, which should help him get drafted higher than expected.

5. Ryan Harris, Notre Dame. He's another prospect with the natural size (6-5, 292) and athleticism you desire, but he does not always seem to always put it to complete use.

Harris makes pretty good use of his hands and can create the type of jolt you look for. But he fails to sustain his blocks long enough. He can be pushed around by bull rushers and takes too long to re-adjust if beaten off the snap.

Harris needs to bulk up and increase his lower body strength. He struggled against smaller, quicker pass rushers.

It would be hard to see him going before the third round.