Kirk Ferentz pleased with No. 3 Iowa football, appreciates fan energy in 23-20 win over No. 4 Penn State

IOWA CITY — No. 3 Iowa versus No. 4 Penn State. Two undefeated, 5-0, teams meeting in a matchup between Big Ten east and west. The Nittany Lions looking to make up for last year's mistakes that led to a 41-21 Iowa victory. The Hawkeyes trying to improve to 6-0 in their home stadium.

And that’s exactly what Iowa did on Saturday. The Hawkeyes came from behind in the fourth quarter to take the lead away from Penn State, the first time the Nittany Lions hadn’t been on top since their first touchdown. Spencer Petras completed a 44-yard touchdown pass to Nico Ragaini with less than seven minutes remaining in the game to put Iowa up 23-20.

With Penn State limping along with a backup quarterback, the Hawkeyes defense was too much for the sophomore Ta’Quan Roberson to overcome. Penn State’s equally strong defense did what they could, but the offense did almost nothing to capitalize on those chances.

Follow along here for postgame updates:

Postgame: Ferentz on the final touchdown and Iowa turning it around in the second half

"They made it really hard on us…but at some point, you have to step up and do something. It was a great play call, great execution. There were a million little things going on that maybe weren’t as dramatic, that was good to see in the second half. Just pleased with the way the guys responded."

"And to be behind like that and keep our foot on the gas I thought was really impressive. They're a good team. We've had tremendous respect for them. Continue to. They're a team that can make things happen pretty quickly if you're not careful. So, again, really happy about that."

Postgame: Ferentz on the defensive efforts against Penn State

"Lots of good efforts defensively up and down the board. Hankins making that stop on fourth down right in front of our bench. Just teasing, we may move him to linebacker. That was good tackle where he just basically stopped the guy. That's really hard to do. Just emblematic. Got a pick on top of it."

Postgame: Ferentz on the team's confidence in Petras

"We’ve had confidence in him, even though he was a little bumpy a year ago. We get to see the players day-by-day and teammates get to each other also. So, they know how invested he is."

"(It was) just executed so well. That’s not an easy throw, and Spencer did a great job, and Nico’s been just so dependable for us."

"Our fans did a great job. They were into the game. We knew they’d be ready to go at the start. They were more ready than we were, just wanted to make sure our team understood, that they can’t play the game for us.

"Pleased for our team," Kirk Ferentz said. "It was a good win for us, certainly our guys have worked hard for that. I’m just really proud of our team. It was a tough game, we knew that coming in. Knew that it would be. Penn State has got a great talent, great athleticism. They've been playing really good football. So, just really proud. We got off to a tough start, slow start. Our guys just kept working, kept pushing through it."

Iowa pulled off the comeback win in front of dozens of high-level recruits. If there were any questions of why gameday visits matter, this answers it.

"You don’t get moments like this every day, Nico Ragaini said about what it feels like to beat Penn State. "It was a mentally draining and physically draining...We fought for it and we deserve it.

"I definitely rank Ohio State the best my freshman year," Matt Hankins said about fans storming the field. "It's always exciting when fans rush but...once you experience the first time, I'm trying to get off the field as quick as possible."

Iowa's quarterback noted that fans storming the field after the game was a great way to celebrate the win, and admits he's never had his head slapped so many times postgame.

The Hawkeyes move to 6-0 on the season and get the better of No. 4 Penn State. Iowa took advantage of the Nittany Lions injured starting quarterback and staged a fourth quarterback comeback, capped by Raga

2:13/Q4: An Iowa interception could end it

Iowa's Matt Hankins picked off Penn State quarterback Ta’Quan Roberson and the Hawkeyes took over close to mid-field with just over two minutes remainin

Penn State needed to convert to keep their scoring chance alive, and Iowa's defense wasn't going to let that happen. The Hawkeyes take over at the Iowa 45-yard line.

Petras completed a 44-yard touchdown pass to Nico Ragaini, and with the point after, Iowa is up by a field goal late in the fourth quarter.

6:35/Q4: Iowa takes over at the 44-yard line

The Hawkeyes defense is doing everything it can to give the ball back to Petras and the offense. And it's working, with Penn State's Jordan Stout forced to kick in the endzone. Iowa is within the 50-yard line with time to make plays.

8:08/Q4: Penn State's defense gets in the way — Penn State 20, Iowa 16

Iowa had a chance to tie the game after that huge catch from Johnson. But Penn State's defense put up a huge stop against the Hawkeyes, holding the Nittany Lions' four-point lead for a little longer.

Capitalizing on good field position, Petras launched a 42-yard pass to Keagan Johnson. He was taken down at the 8-yard line.

Iowa may have punted away again, but that doesn't mean they're giving away good field position to Penn State. Tory Taylor just kicked a 53-yard punt, and Ivory Kelly-Martin chased it down to make the Nittany Lions start on the 2-yard line

End of the third quarter: Penn State 20, Iowa 13

Penn State punted the ball on their first drive after Iowa's field goal, and the Hawkeyes take over possession on the Iowa 15.

1:36/Q3: Iowa inches closer with first score of second half — Penn State 20, Iowa 13

Iowa took the ball 45 yards on 10 player and cut 5:04 off the clock, but the Hawkeyes once again had to settle for a field goal. They're one touchdown from tying Penn State thanks to a 48-yard kick from Caleb Shudak.

Iowa kept the Nittany Lions out of the endzone, but Penn State did get close enough for Jordan Stout to make a 44-yard field goal. They extend their lead to 10 points and took 3:19 off the clock in the process.

Clifford is officially out for Penn State and joins his teammates on the sidelines in plain clothes with his right arm wrapped. The Nittany Lions started the half with possession, but the first drive looked much like the end of the second quarter did.

Penn State was the more dominant offense in the first half, but Iowa has a chance to capitalize on the Nittany Lions' quarterback woes. The Hawkeyes defense is still playing at the caliber it has all game, and on the other side of the ball, Penn State has struggled to put together a drive without a false start call since Clifford left

Thinks went from bad to worse for Penn State's backup quarterback. He tried to throw downfield and, by overthrowing his receiver, sent the ball right into the hand's of Iowa's Riley Moss. He needed help off the field after the play, and it was all in vain, with the Hawkeyes forced to punt on fourth-and-2.

Penn State's starting quarterback, Sean Clifford, headed to the team's locker room, and it exposed how much the Nittany Lions rely on him. Ta'Quan Roberson took over behind center. How did that go? Three consecutive false starts and Penn State punted.

7:08/Q2: Charlie Jones gets Iowa its first touchdown — Penn State 17, Iowa 10

Jones reeled in a 9-yard pass from Petras and stretched into the corner of the endzone as he was tackled to give Iowa its first touchdown of the game. The Hawkeyes went 75 yards on 11 plays while taking 5:23 off the clock.

Nittany Lions failed to convert a third and seven on the 14-yard line and settled for a field goal. That puts Penn State up by two touchdowns as Iowa gets the ball back.

End of the first quarter: Penn State 14, Iowa 3

Iowa has gotten close, but has yet to convert a drive into a touchdown. The Hawkeyes defense is putting steady pressure on Penn State - but, the Nittany Lions are giving it right back to Iowa.

Penn State's quarterback Sean Clifford took matters into his own hands, running four yards for a Nittany Lions touchdown. Penn State went 39 yards on 4 plays and took 1:23 off the clock.

4:44/Q1: Well, that didn't last long

Scratch that, Penn State got the ball back. Jaquan Brisker intercepted Petras, giving the Nittany Lions the ball back at the Iowa 39-yard line. Clifford followed that with a 30-yard pass to KeAndre Lambert-Smith, and play is currently stopped as Lambert-Smith is down near the endzone with an apparent knee injury.

After being called for pass interference - and giving Penn State 15 free yards that led to a touchdown - Jack Zoerner made up for his mistakes in a big way. He picked off Penn State quarterback Sean Clifford in the endzone for a touchback.

Iowa gives the ball back to Penn State after a 3-and-out that includes a run for a loss of one and another sack, this time for a loss of two yards.

8:37/Q1: Penn State gets the first touchdown — Penn State 7, Iowa 3

Nittany Lions running back Noah Cain forced his way into the endzone to put Penn State on top. Penn State travels 75 yards on nine plays and takes 2:31 off the clock.

This is certainly starting as a defensive game. Iowa was forced to punt away on their first drive, but Penn State didn't even have the ball for a full play before Jestin Jacobs intercepted a Sean Clifford pass at the 8-yard line. Penn State wasn't about to let Iowa score that easily, with Arnold Ebiketie sacking Spencer Petras for a loss. Iowa sunk the 34-yard field goal to take an early lead.

Penn State defensive tackle limped off the field after suffering an injury early in the game.

Here's the good news: Iowa's team is probably the healthiest they've been. Really nothing to report here. Bad news? Penn State is also pretty healthy. The Nittany Lions' main running back, Noah Cain, has been on and off this season, but he's suited up for warmups.

The game hasn't even begun, and Penn State fans are already upset about the choice of head referee. John O'Neill will be the number one official today, and he's well-respected by Kirk Ferentz. Curious about how the Nittany Lions faithful are taking the news? Take a look through the replies to this tweet to find out.

Did you know that Iowa's roster has exactly one player from Pennsylvania and Penn State's roster has exactly one player from Iowa? It's almost as if they joined a Big Ten exchange program.

Jake Pinegar, one of Penn State's kickers, originally hails from Ankeny. He played for Jerry Pezzetti - Iowa's all-time winningest high school coach - at Ankeny Centennial before starting at placekicker as a true freshman. Iowa defensive back Terry Roberts joined the Hawkeyes from Erie, Pa. He played high school football at Cathedral Prep, which is about three hours northwest of Penn State.
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Alyssa Hertel is a college sports recruiting reporter for the Des Moines Register. Contact Alyssa at [email protected] or on Twitter @AlyssaHertel.