Evan said it best when talking about the OLB situation for the Packers, there is "lots of potential" but "depth is a serious concern." In the past the Packers have addressed this by taking chances on undrafted rookie free agents, typically players who have played 4-3 defensive end in college but have the athleticism to make the transition to 3-4 outside linebacker. This strategy often results in young man who is man crush of countless Packer fans during training camp and then does little to nothing during the regular season, such as Frank Zombo, Vic So’oto, and Dezman Moses. In recent years the Packers have been showing a stronger commitment to improving this position. This commitment was first shown by drafting an OLB prospect in the 2011 draft instead of solely relying on undrafted talent. This was followed up by dipping into the first round to find a long term starter. Now that depth seems to be the main issue it’s not unreasonable to think that the Packers may test the free agent waters for more proven talent that could help bolster the rotation of OLB’s.
One interesting option could be Victor Butler of the Dallas Cowboys. Rotoworld listed Butler as "free-agent sleeper" this year due to his ability log 11 regular season sacks while getting limited snaps behind DeMarcus Ware and Anthony Spencer. PFF also rates Butler highly giving him a +7.2 rating for 2012. Butler has showed that he can be effective coming off the bench and being part of a rotation and could be an excellent complement to Matthews and Perry.
Another solid option highlighted by PFF would be Antwan Barnes of the San Diego Chargers. Barnes is another relatively young player who was able to produce a good amount of pass rush while playing behind Shaun Phillips. Barnes is undersized (6’ 1" 251 lbs) but has good speed for coverage (he ran a 4.43 40 yard dash at his combine). Barnes got an overall grade of -0.2 from PFF for 2012, but they do note that he has not received a negative run defense grade from the site during 2012.
The best part about targeting players like Butler and Barnes is that they should come at a reduced cost with bigger names like Anthony Spencer, Paul Kruger, and Connor Barwin available. Yet both Barnes and Butler would be a huge upgrade over the likes of Zombo or Walden, and provide the rotation needed to help keep Clay Matthews healthy and give Perry the time needed to develop.