Katzenmoyer intercepted a fourth-quarter pass to end Iowa's last hope and also threw a block on the decisive touchdown as the Buckeyes shut down Tavian Banks and the 11th-ranked Hawkeyes 23-7 Saturday.
"Katzenmoyer probably won the Butkus Award today," Banks said after being held to 84 yards, 125 below his national-best 209 per game. "He was all over the field. He's the real deal. He was probably in our backfield more than I was."
Katzenmoyer said he wasn't stumping for any awards.
"I didn't want to go out and make a statement," he said. "I wanted the defense to make the statement."
Katzenmoyer's crunching block on Eric Thigpen paved the way for the first of Michael Wiley's two touchdown runs, a 1-yard burst in the second quarter that put Ohio State ahead 10-0.
"It was interesting on offense. It's nice to be the hitter instead of the hittee," Katzenmoyer said. "I hope to get the ball in that situation someday."
On defense, he had nine solos and two assisted tackles, two tackles for a loss and broke up a pass.
"He showed you today why I think he's the best linebacker in the country," Ohio State coach John Cooper said.
In the Big Ten opener for both teams, Ohio State (5-0) was never in trouble after the defense held Iowa's offense to 94 yards in the first half, while the Buckeyes were building the 10-0 lead.
Iowa (4-1) came into the game averaging 568 yards, 310 rushing, and 55.3 points. But the Hawkeyes mustered just 106 yards rushing and 308 overall. Iowa didn't top 250 yards until going to a hurry-up offense in the waning minutes with the game out of reach.
"They had been putting up incredible numbers," Katzenmoyer said. "And we came out ready to play. It was our best defensive effort of the year."
Banks, leading the nation in scoring (13 touchdowns in four games) in addition to rushing, never got untracked. He came in averaging 9.1 yards a carry.
"He's a solid back, but we just had his number," Katzenmoyer said. "It frustrated him and it frustrated them."
Iowa coach Hayden Fry said, "To stop Banks they used everybody but the kitchen sink. And we didn't block nine guys very well."
Ohio State extended its winning streak to six, while putting an end to Iowa streaks of seven in a row overall and five straight on the road.
Pepe Pearson had 19 carries for 106 yards and Wiley contributed 85 on 14 attempts as the Buckeyes piled up 238 yards rushing, 85 over their average.
Ohio State's 10-0 halftime lead was a small victory for the Hawkeyes. In the last two meetings the Buckeyes outscored Iowa 87-13 just in the first half.
One play after Ohio State quarterback Stanley Jackson hopped to the sidelines with a sprained ankle early in the second quarter, Dan Stultz kicked a 36-yard field goal.
Iowa drove to the Buckeyes' 25 on its next possession, but Zach Bromert's 42-yard field goal attempt was blocked by Percy King.
"Our players might not be as good as we've had in the past, but I thought defensive coordinator Fred Pagac and his staff did a good job and we really got after them on defense," Cooper said.
Joe Germaine came in for Jackson and hit all five of his attempts for 54 yards in a 66-yard drive that ended with Wiley taking a pitch and cutting inside Katzenmoyer's crushing block on Eric Thigpen to score.
Jackson returned to play every offensive down of the second half, completing 7-of-16 passes for 83 yards. He found David Boston for a 6-yard scoring toss on the Buckeyes' first possession of the third quarter to push the lead to 16-0.
Iowa's only points came on Matt Sherman's 4-yard pass to Austin Wheatley. Sherman completed 18-of-37 passes for 189 yards and one interception.
"It was frustrating for me," Sherman said. "They had me guessing a lot."
That one mistake was a big one. Driving in Ohio State territory midway through the fourth quarter, Sherman's short pass went off the hands of receiver Tim Dwight in the left flat, then ricocheted off the fingers of defender Antoine Winfield before Katzenmoyer picked it off.
"Sideline to sideline," Fry said, "he has as good a range as any
linebacker I've ever seen."