Kirk Ferentz knows Iowa football fans are smart.

So when the Hawkeye faithful in attendance for Iowa’s 23-20 win over Penn State at Kinnick Stadium saw Nittany Lion defensive players repeatedly go down with injuries after big plays by the Iowa offense, Ferentz understood why boos were heard from the stands.

“I thought they smelled a rat, I guess,” Ferentz said on Tuesday. “So they responded the way they responded.”

Trainers helped Penn State defenders off the field with injuries five different times during the top-five matchup over the weekend.

These injuries often came after positive plays by Iowa’s offense.

“You’re hearing the boos,” analyst Joel Klatt said on the FOX broadcast. “You know why you’re hearing boos? Every time Iowa gains more than 10 yards or 12 yards, there’s somebody who goes down on the Penn State defense. There’s been an injury after every big play that Iowa has had. The fans here recognize that, and they’re upset by it.”

Nittany Lion safety Jaquan Brisker left the game with an apparent left shoulder injury late in the first quarter right after Iowa running back Tyler Goodson ripped off a 20-yard run. Brisker later returned to the game.

Later in the third quarter, Penn State defensive lineman Arnold Ebiketie fell down without being hit and needed a trainer’s assistance after an 18-yard run by Goodson. Iowa special teams coordinator LeVar Woods fell down on the sideline to mock the situation. Ebiketie later returned to the game.

We know Penn State had some legitimate injuries in this game, but this 54 seconds of video was especially entertaining.

I believe this player walked off the field shortly after this clip ends… Let’s just say the Iowa coaching staff wasn’t buying this one. pic.twitter.com/YC6RPQaIi8

— Mark Freund (@MarkFreundTV) October 10, 2021

Defensive tackle Dvon Ellies returned to the game in the second half after going down with an injury in the middle of the second quarter.

Boos intensified from the stands after each injury. Hawkeye fans seemed to think the Nittany Lions were faking injuries in order to disrupt the offense’s tempo.

“I do have a little bit of a hard time with our players getting hurt, and the fans and the coaches and the staff booing our players,” Penn State coach James Franklin said postgame. “They don’t run a tempo offense. It was not part of our plan… I don’t think that’s the right thing for college football, booing guys when they get hurt, however it looks.”

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Ferentz was asked about the situation on Tuesday. The 23rd-year head Hawkeye came to the support of Iowa fans.

And he didn’t hold back while doing it.

“Football’s a hard, competitive, tough game and fans are into it just like everybody else is into it,” Ferentz said. “First of all, I know a couple [Penn State] players were legitimately hurt [including starting quarterback Sean Clifford], I know that … So I hope those guys are well, I don’t know what their status is, nobody wants to see anybody get hurt. Nobody.

“But I think probably [the booing] is a reaction to there were a couple guys that were down for the count and then were back a play or two later. Our fans aren’t stupid. They’re watching. They know what’s going on. I’ve been here 23 years. I think that’s only the second time we have seen that kind of stuff going on.

“I know it’s a topic nationally right now. It was one of the discussions of the rules. Nobody knows the answer to it … There are two people in our building that have been places where ‘scuba’ and ‘turtle’ were the code words [for a player to fake an injury]. So it goes on. We don’t coach it.”