Other than the knee issue, Harrison's as healthy as he's been in three years. (US PRESSWIRE)

As it stands, second-year linebacker Chris Carter is the Steelers' "other" outside linebacker opposite LaMarr Woodley. That's because five-time Pro Bowler James Harrison underwent arthroscopic knee surgery last week and it's unclear if he'll be ready for the regular-season opener against the Broncos.

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Harrison, who has been on the physically-unable-to-perform list since July 25 and hasn't taken part in a contact practice since last season, told reporters Tuesday that while working on his conditioning early in camp "the knee blew up" and he "couldn't let it go any longer (without surgery)."

Unlike Mike Wallace, who's set to rejoin the team in the coming days but has no experience in Todd Haley's offense, Harrison is intimately familiar with Dick LeBeau's scheme. And it's for that reason that he feels he'll be ready to go when the Steelers travel to Denver to face Peyton Manning.

“I might need a little prep, we got a couple of new things (on defense), but other than that I think I’ll be all right,” he said. “You’ve got to get back in timing with the other guys and everything else, and a few days of practice would help.”

If there's good news, it's this: Harrison's agent, Bill Parise, said before the surgery that the Steelers linebacker is in great shape.

"With the exception of this little knee thing, James is probably healthier now that he's been in three years,” Parise said according to the TimesOnline.com's Mike Bires. “He's extremely fit. He just has to get this irritation behind his knee cap cleared up. That's what's causing the swelling, and (the Steelers) just want to get rid of that. So we might even look at doing a scope of that to get it cleaned up. We'll just have to wait see how it plays out.”

That's a pretty big exception but coach Mike Tomlin likes to point out that Harrison has been known to recover quickly. While we wait for some Mr. Miyagi-style healing to take place, Carter's the man. He's played well in two preseason games but he's not nearly the pass rusher that Harrison is. Then again, he doesn't have to be. He just needs to do his job, allow his teammates to do theirs, and hope that the Steelers' new-fangled offense can take care of the rest.

For now, Carter, a fifth-round pick out of Fresno State, doesn't sound worried.

“James is fine,” he told Bires. “You know, he does his thing. James is the consummate professional. He knows what he needs to get his body just right. I have no concerns about James.”

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