The Pittsburgh Steelers have always been known for their defense: the "Steel Curtain" of the 1970s when they won four Super Bowl championships, and their most recent titles in '06 and '09.
Troy Polamalu has been the most important player on the Steelers defense since he was drafted in the first-round out of USC in 2003.
The 31-year-old is all over the playing field with his instincts taking him to the line of scrimmage, and at times jumping over lineman to get to the quarterback. He is a great leader on defense and allows free safety Ryan Clark to play back.
Polamalu makes the clutch play when Pittsburgh needs it the most. There is no denying how great of a player No. 43 is on the field.
However, the issue is his ability to stay on the field. Some can argue that his aggressiveness leads to injuries, yet it's tough to criticize Polamalu's style of play, given that it has been so instrumental to the Steelers' defensive success throughout his career. Still, the injuries are racking up.
Polamalu left the Steelers' Week 5 win against the Eagles as he re-aggravated a calf injury that has limited him to only two games this season. He originally suffered the injury during the playoffs last season.
Pittsburgh has struggled greatly without the services of their Pro Bowl safety as they have blown two critical leads in the fourth quarter. In Oakland, the Steelers held a 10-point lead in the final minutes of the game but were unable to hold on as the Raiders came back to win 34-31. Most recently in Tennessee, the Steelers held a touchdown lead in the fourth quarter but surrendered it and the game to the Titans, 26-23.
Polamalu was inactive for both games
Polamalu's aggressive play is exciting to watch, but as he gets older his body may not be able to keep up with his instincts. It may be time for the Steelers to think about their long-term replacement options for him.
It's similar to a team who is looking to find an eventual replacement for their franchise quarterback. The process can take a few years, but the Steelers are better off trying to find one sooner rather than later so that there is an easy transition.
Don't mistake this as an interpretation that Polamalu is finished. He has a few solid years ahead of him.
But the question is whether he get back to 100 percent, and more importantly, will he be healthy enough to continue to play at an elite level in the next two or three seasons.
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