How the Eagles' offense lines up

The Eagles played with three wide receivers 51 percent of the time last season. (Yong Kim/Staff file photo)

While the Eagles are expected to address defense in free agency, offensive personnel will look similar to the group that took the field in 2010.

Assuming Kevin Kolb gets dealt, the Birds will need to add a backup quarterback. If Jerome Harrison bolts, a No. 2 running back could be necessary also. And if there's a playmaker that Andy Reid and Howie Roseman believe is worth bringing aboard, that wouldn't be a huge surprise either.

But today, let's look at how the different pieces fit together for the Eagles on offense.

The crew over at Football Outsiders recently released a breakdown of how teams lined up their wide receivers last season.

Below are some notes on their findings, along with some of my thoughts sprinkled in:

0-1 WR

The Eagles went with zero or one wide receiver on just 3 percent of their offensive plays last year. Only the Lions and Colts did so less frequently.

2 WR

The Birds lined up with two wide receivers on 34 percent of their plays. Leaguewide, teams did so 38 percent of the time, and eight teams lined up with two wide receivers less often than the Eagles. But the Birds were very efficient in these formations, ranking fourth in performance with two receivers, according to Football Outsiders' metrics.

3 WR

The Eagles' most common offensive formation was one running back, three wide receivers and one tight end. They played with three wide receivers 51 percent of the time. So while we sometimes refer to DeSean Jackson and Jeremy Maclin as the starters, Jason Avant probably belongs in that group also.

Only four teams (the Bengals, Broncos, Lions and Colts) went with three wide receiver formations more often than the Eagles, and only four teams performed better in those formations (the Chargers, Patriots, Bucs and Packers).

Leaguewide, teams went with three receivers on 43 percent of overall plays, emphasizing the importance of the nickel cornerback. In the Eagles' case, they are comfortable with Joselio Hanson, but the numbers also reflect the importance of cornerback depth. One injury means the fourth cornerback should be ready to play nearly half of the snaps in any given game.

4-5 WR

This formation relates to the possibility of the Eagles taking a shot on Plaxico Burress. Only five teams (the Cardinals, Bills, Packers, Saints and Steelers) used four or five receivers more often than the Birds, who did so on 12 percent of their offensive plays. In these formations, the Eagles ranked 11th in performance.

Let's say (hypothetically) the Eagles brought on Burress and wanted to use four receiver formations more often. It would likely mean a decrease in snaps for either LeSean McCoy or Brent Celek (and obviously Riley Cooper too).

In 2008, the Eagles used four receivers on 15 percent of their offensive plays (fifth-most), and in 2009, that number was 13 percent (third-most). So their use of four receivers has remained relatively consistent during the past three seasons. But if they added Burress or wanted Cooper to have an expanded role, that number could increase in 2011.

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