No coordinator has carried his team more than the longest tenured coordinator in the nation: Phil Parker. Iowa's offensive woes have forced Parker and his defensive unit to do more than what is asked of a typical defensive unit, but they have risen to the occasion time and time again.
Since Parker took over in 2012, the Iowa defensive unit has ranked in the top ten in total defense and points allowed multiple times, including a No. 1 ranking in yards per play in 2023.
Iowa's defense under the tutelage of Phil Parker has ranked in the top 20 in every season for the last decade, making up for the program's shortcomings on offense.
Last season was a "down" season by Iowa standards, but the unit still ranked No. 11 overall in scoring defense (17.8 points per game) and No. 20 in total defense (318.4 yards per game average).
After another solid season at the helm of the defense, Parker finally earned recognition, ranking as the No. 1 overall defensive coordinator on a preseason rankings list.
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On3 Sports' Andy Staples ranked Parker as his No. 1 defensive coordinator ahead of former Ohio State defensive coordinator and 2024 National Champion, Jim Knowles.
Staples' reasoning behind his decision to rank Parker No. 1 overall on his list is because "no other coordinator has done more than Parker has through Iowa's recent half-decade of offensive dysfunction."
Staples acknowledged that last season was a down year on the defensive end for the Hawkeyes, but Parker's defense will respond. He also stated the unit is a candidate to have a bounce-back year this upcoming season.
If transfer quarterback Mark Gronowski and the Iowa offense can improve this season, that makes the Iowa defense even scarier because they will not have to be on the field as much as in the past.