Harrison, one of the team's signature defensive players, will be 35 years old when the NFL opens the 2013 season. He's also going to count $10 million against the salary cap in 2013.
Given his drop in production (only six sacks in 2012 after having nine in 2011 and 10.5 in 2010), the Steelers may need to go with a less expensive and younger alternative.
This would be an easy call if Harrison weren't such a devastating defender when he's fully on his game.
The problem is his game has eroded due to some injuries and the natural march of age. With Jason Worilds, a much younger player that has impressed in limited action, seemingly ready to take over, the Steelers must make the difficult decision to say farewell.
The cap savings is the other part of the equation. If Pittsburgh can recoup the money due Harrison, they can plug some other leaks on their team (inside linebacker, running back or safety) without having to restructure every major player on the team.
In the end, this should go the same way things did with Joey Porter. Harrison's age and limited effectiveness have put him on the outside of the bubble. It's time to say goodbye.