Iowa kicked a game-winning field goal to knock off Jim Harbaugh and Michigan. The same scenario happened when they faced off in 1985 and Harbaugh was the Wolverines QB. (0:35)

IOWA CITY, Iowa -- You don't have to be a student of Iowa football history to appreciate how the Hawkeyes upset No. 3 Michigan 14-13 on Saturday night. The game will stand on its own until the youngest Hawkeyes fan among the 70,585 at Kinnick Stadium is old and gray.

Iowa freshman kicker Keith Duncan drilled a 33-yard field goal through the uprights in the south end zone as time expired, then sprinted 35 yards in the opposite direction before being buried beneath a joyous, heaving mass of teammates.

"I just took off," Duncan said. "I didn't really know what to do. You don't really practice those things."

The game will stand on its own because it helped stand the College Football Playoff ranking on its head. Michigan (9-1) joined No. 2 Clemson and No. 4 Washington among the day's upset victims. It stood the Big Ten East on its ear, because No. 10 Penn State, with one loss, will win the division if Ohio State beats Michigan.

But enough about Saturday. If you remember that on this same field 31 years ago -- the opposite end zone but the same field -- No. 1 Iowa defeated No. 2 Michigan, 12-10, when the sainted Rob Houghtlin drilled a 29-yard field goal, then you know what this game will mean in Hawkeyes history. The angels still sing in this state every time Houghtlin's name is said aloud. You might even remember that the Wolverines quarterback that day, Jim Harbaugh, had to relive the same devastating finish Saturday night.

You could count the people who saw both games from the field on one hand. But you would include both head coaches. Kirk Ferentz, the Hawkeyes' boss, was their 30-year-old offensive line coach the first time this happened.

"The electricity in Kinnick that date in '85, late kickoff, it was special just like tonight," Ferentz said.

Iowa celebrated its thrilling -- and stunning -- win over Michigan that helped shake up the College Football Playoff. Charlie Neibergall/AP Photo

The beauty of an Upset Saturday is that you never know when they are going to arrive. This game didn't appear to be a candidate. Michigan seeming to grow stronger and faster with every week. The Wolverines had won seven of their nine games by at least 17 points, and humiliated Maryland, 59-3, a week ago.

Iowa, meanwhile, had lost at No. 10 Penn State 41-14 in a game that wasn't as close as the score indicated. The loss dropped the Hawkeyes, Big Ten West champions a year ago, to 5-4.

"A week ago at this time, none of us were having much fun," said Ferentz, the human carpenter's level. " ... Really simply, you've only got two options. You surrender and mope and feel sorry for yourself, or you do something about it."

The Hawkeyes awoke Sunday morning and, as if they were a locker room of 85 Richard Shermans, they forgot. They moved on to the next play.

They practiced well. They talked about how if they could find a way to beat Michigan, the fans would storm the field. On Thursday, senior quarterback C.J. Beathard checked in with junior linebacker Josey Jewell. "We're ready to go," Jewell said to him. "Give us 14 points and we'll win the game."

Jewell smiled sheepishly when asked about it. He has never said anything like that before.

"I just saw it in people's eyes," Jewell said. "People believed. People knew. We're not out of this yet."

Iowa got its 14, just not in the traditional two-touchdown fashion: a safety, a touchdown, a missed two-point conversion, and two field goals. Everything else about this win looked traditional. Take the defenses. Michigan limited Iowa to 230 total yards, which was 29 more than the Wolverines gained. Think about that: the Michigan offense came into the game averaging 497.1 yards. Not only did the Wolverines gain nearly 300 yards below their average, the two teams combined fell well short of it, too.

"I told the offense that this would probably not be pretty," Iowa offensive coordinator Greg Davis said.

The Hawkeyes won because they made fewer mistakes. Michigan, which had turned the ball over only six times in nine games, gave up two in the second half.

"Little miscommunications," Michigan quarterback Wilton Speight said, "stuff in the huddle, obviously that starts with me, guys being able to hear play calls and stuff, because they [the Iowa fans] were going nuts."

They won because junior back Akrum Wadley slithered around and through the Wolverines to rush for 115 yards, as well as five receptions for 52 yards and that touchdown.

They won because freshman corner Manny Rugamba, pressed into action on the opposite side of All-American Desmond King, responded with three passes broken up and an interception.

With Michigan leading 10-0 late in the first half, Iowa defensive tackle Jaleel Johnson burst through the line and tackled Wolverines tailback De'Veon Smith for a safety. The Hawkeyes took the ensuing kick and drove 52 yards for a touchdown. Ferentz, rarely a riverboat gambler, went for two to tie the score, but Adrian Falconer dropped Beathard's pass in the end zone.

But Duncan made two field goals in the second half. The first, a 25-yarder, capitalized on Michigan fullback Khalid Hill's fumble of the second-half kickoff. That gave Iowa an 11-10 lead, the first time Michigan had trailed after halftime since the Colorado game in Week 3.

The second one changed Duncan's life. Actually, it changed the life of everyone wearing black and gold, from the players to the fans.

"That's why you do this, whether it's in Kinnick or a parking lot," Ferentz said. "The feeling that everybody had in the locker room, of achievement, the feeling of doing something really significant during the course of the week, and having it show up on the field, that's what's life is all about."

Forget the parking lot. It had to be in Kinnick, against Michigan, thanks to a field goal as time expired. History demanded it be just so.