2012 NFL Draft Grades: Teams That Aced the Fourth Round

Day 3 of the 2012 NFL Draft is in full swing, as the annual selection process has passed its halfway point with the conclusion of the fourth round.

A number of notable prospects came off the board early Saturday, including Michigan State quarterback Kirk Cousins and Wisconsin wide receiver Nick Toon, who were drafted to the Washington Redskins and New Orleans Saints respectively.

So who had the best fourth round of all?

Here are the final day's early winners, who aced the fourth round:

Detroit Lions' Fourth Round Pick: Ronnell Lewis, OLB, Oklahoma

The Detroit Lions added a gifted pass-rusher in Oklahoma's Ronnell Lewis with the 125th overall pick in the draft. The 6'1", 253-pound Lewis had 59 tackles last season for the Sooners and has ideal size and length for his position, according to most scouts and experts.

Lewis' strength was on display at this year's combine, where he led all linebackers on the bench press, posting an impressive 36 reps of 225 pounds. Though his durability at the next level has come into question because of some nagging back problems, Lewis is a phenomenal tackler and hard worker who will pay off for Detroit in more ways than one.

Grade: A+

Pittsburgh Steelers' Fourth Round Pick: Alameda Ta'amu, DT, Washington

Pittsburgh greatly improved its defensive front by taking Washington's Alameda Ta'amu in the fourth round with the 109th overall selection. Ta'amu was among the top 10 defensive tackles in this year's draft according to many and is an absolute monster against the run.

The Steelers are known for their vaunted 3-4 defense, which puts added pressure on the nose tackle to step up. Ta'amu promises to become Pittsburgh's anchor up front on defense for years to come, where he will be surrounded by exceptional play-making talent. 

Grade: A

Miami Dolphins' Fourth Round Pick: Lamar Miller, RB, Miami

The Dolphins made waves in Miami when they took local running back prospect Lamar Miller with the day's second pick, 97th overall. Miller is young and relatively unproven, but he rushed for a solid 1,272 yards and nine touchdowns in 2011 with the Miami Hurricanes in the ACC.

Although the Dolphins already have a starting back in Reggie Bush, the former USC Trojan is prone to injury and Miller was simply to too quick and elusive at his position for Miami to pass on him. It wasn't a huge need coming into the draft, but the Dolphins improved their offensive line considerably with their fourth round pick.

Grade: A-

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