Posted by ESPN.com's Adam Rittenberg
Biggest reason for hope -- A lot coming back on defense
Iowa returns eight starters from a unit that ranked fifth nationally in points allowed (13 ppg) and 12th in yards allowed (291.3 ypg). Although defensive tackles Mitch King and Matt Kroul will be missed, the Hawkeyes boast plenty of playmakers in linebacker Pat Angerer, cornerback Amari Spievey, safety Tyler Sash and others. Iowa led the Big Ten with 32 takeaways last fall, and returning players accounted for all but six of those interceptions or fumbles. If defensive ends Adrian Claborn and Christian Ballard step up to carry the load up front, Iowa should have arguably the Big Ten's top defense in 2009.
Biggest reason for concern -- No Shonn Greene
Greene was the focal point for the Iowa offense last fall and turned in one of the best seasons for a running back in recent Big Ten history. The Hawkeyes have Jewel Hampton and others coming back, but we don't know how those players will handle featured roles. Iowa's offensive line looks pretty solid and quarterback Ricky Stanzi made strides during the offseason, but the wide receiver/tight end spots raise some concern. Andy Brodell is a key loss, and Derrell Johnson-Koulianos didn't have the spring the coaches had hoped he would. Tight end Tony Moeaki comes off yet another injury, and while he could be a reliable target, his health history is worrisome. Iowa needs some bona fide playmakers to emerge around Stanzi this summer.