The Pittsburgh Steelers' defense will again be missing two key cogs, as James Harrison and Troy Polamalu will apparently be absent again for Sunday's game against the Oakland Raiders.

Harrison still hasn't played after undergoing arthroscopic surgery on Aug. 15, while Polamalu was able to play Week 1 against Denver, but has been out since with a calf injury. Ryan Mundy will continue to replace Polamalu in the secondary while Jason Worilds, who missed the preseason with an injury of his own, will likely start over Chris Carter in Harrison's linebacker spot.

This isn't the end of the world for the Steelers' defense: they're coming off a performance where they held the New York Jets to only ten points without the pair, and face the lowly Raiders in their matchup next week before a bye week where both players will have an opportunity to heal. When the Steelers return to play Week 5, they'll hope to have Harrison and Polamalu as well as running back Rashard Mendenhall, who has yet to suit up this season.

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