Just as the Steelers welcome the possible return of safety Troy Polamalu this week, it appears they have lost the services of defensive end Aaron Smith.

Smith's right shoulder was injured in Detroit Sunday and coach Mike Tomlin said today it "potentially could be significant."

Tomlin said the injury potentially could keep Smith out for awhile, pending the result of tests today.

The Steelers regard Smith as the best 3-4 end in football.

Tomlin said Ziggy Hood, their first-round draft choice, is not yet ready to replace Smith as the starter and they would do so "by committee."

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