DeCastro had already earned a spot in the starting lineup. Now he's scheduled to undergo surgery on his knee. (US Presswire)

The Steelers' commitment to bolster the offensive line and protect their $100 million investment in quarterback Ben Roethlisberger took a blow Saturday when rookie first-round pick David DeCastro suffered a serious knee injury in the team's preseason game against the Bills. The severity of the injury was unknown at the time, but it's never a good sign when a player leaves the field on a cart. And any fears that the guard from Stanford's season might be over before it began were only exacerbated when coach Mike Tomlin called the injury "potentially severe" during his postgame comments.

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DeCastro, who reportedly suffered a torn medial collateral ligament, a dislocated knee cap and damage to his patellar tendon (but his anterior cruciate ligament is intact), will have surgery Wednesday Tomlin said. But it appears the Steelers have avoided the worst-case scenario: the rookie isn't headed for injured reserve.

“Fortunately, he’s not done for the year,” Steelers offensive line coach Sean Kugler told the Pittsburgh Tribune-Review. “It is going to be a long comeback for him, but just the fact that it wasn’t something devastating that ended his year (is positive.)”

Kugler added: “I think David will be back this year, and he’s intent on doing that; I know that."

Which suggest there's a possibility that, should rehab take longer than expected, DeCastro wouldn't return in time for the 2012 season. It's reason enough to wonder if the Steelers should go into the season with what essentially will be a 52-man roster plus DeCastro. After all, his roster spot could go to another lineman capable of contributing on game days. Then again, if you're at all familiar with Pittsburgh's offensive line, it's a group that, for whatever reason, is prone to injury at rates seemingly higher than the rest of the league. By December, the Steelers could very much need DeCastro.

For now, the right guard job falls to Ramon Foster, who started 14 games in 2011.

“I trust Ramon more than anybody else,” Kugler said.

Foster, while nowhere near as athletic as DeCastro, has been serviceable as an interior lineman. "It's just good to be that guy," he said. "'The more you can do' is one of Coach Mike Tomlin's main things, and it's shown a lot lately -- at least since I've been here and with other guys, too."

Tomlin, who often touts the "next man up" Steelers philosophy, conceded that DeCastro's situation was tough.

“The guy is injured and you feel sorry for him on a personal level, professionally,” he said before adding, “We understand this is as much a part of the game as blocking and tackling, so we move on.”

Backup center Doug Legursky echoed Tomlin's sentiments: "Unfortunately, (the injury) happened, but the next man will step up and fill the position. That's what we've shown through the years. The next man has to step up and the standard is the standard. That's what we embrace around here."

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