Steelers cornerback Deshea Townsend has been upgraded to probable despite a sprained neck and is scheduled to start Sunday against the Minnesota Vikings. Townsend got a scare last Sunday when he went numb in his neck and spine after hitting Bears quarterback Kyle Orton on a blitz. After a series of tests, no neurological damage was found and Townsend was allowed to return to practice this week. Townsend began the week listed as questionable on Pittsburgh's injury report. Left tackle Marvel Smith will miss his fourth game in five weeks with an injured ankle and will be replaced again by rookie Trai Essex. Smith was doubtful earlier in the week, but was downgraded to out after not practicing.