WEST LAFAYETTE, Ind. — All Kaleb Johnson saw on Saturday was green grass.

The true freshman running back exploded from the line of scrimmage on the second play of the second half against Purdue at Ross-Ade Stadium, going nearly untouched for 75 yards and a touchdown. His score helped the Hawkeyes seal a 24-3 win over the Boilermakers.

“I just saw my line blocking, and then I saw green grass,” Johnson said. “I saw it, and I just went. It was all green grass for me, and I took advantage of it.”

Johnson’s 75-yard touchdown run was the longest by a Hawkeye since Tyler Goodson registered an 80-yard rush against Wisconsin in 2020.

The touchdown helped punctuate a career game for Johnson. The Hamilton, Ohio, product gained a career-high 200 yards on 22 carries, becoming the first Hawkeye since Akrum Wadley in 2015 to do so in a single game.

Johnson is also the first Iowa freshman to have two 100-yard rushing games in one season.

“He’s got the size and speed, we all kind of knew that,” quarterback Spencer Petras said of Johnson. “I think the challenge [offensive coordinator Brian Ferentz] had for him after last game was just finishing every run. He doesn’t necessarily know how strong he is sometimes, I think. What I really loved is seeing him finishing all his runs today.

“I think, as his confidence continues to grow, he’ll continue to run through tackles as opposed to assuming the run is over, which I think might’ve happened on a couple runs last week.”

Along with pushes from his offensive coordinator, Johnson said running backs coach Ladell Betts has been pushing him to break through tackles in practice.

Johnson averaged 7.2 yards per attempt against Northwestern on Oct. 29. After a week of practice, he averaged 9.1 yards per carry against Purdue.

“[Betts] tells me before practice all the time, ‘Always finish runs,’” Johnson said. “Every time I leave the hole, it’s always been some bag that he has hit us with in assignments to finish. So, I feel like that’s made a big difference.”

Johnson didn’t expect to have this much production early in his Hawkeye career. The 19-year-old from decommitted from California in 2021 to come to Iowa following the then-No.3 Hawkeyes’ 23-20 victory over the then-No. 2 Penn State Nittany Lions.

“It was just the atmosphere,” Johnson said of what brought him to Iowa. “It already felt like home. They made me feel at home. I felt really happy and really surprised with how Iowa made me feel … I felt like I could play here, and I ran with it.”

Though he’s listed as the third-string running back on Iowa’s weekly depth charts, Johnson leads the Hawkeyes with 563 rushing yards this season.

No matter if he’s starting or watching from the sidelines, however, Johnson has the same sense of responsibility.

“Every week I feel like I’m responsible,” Johnson said. “To me, it’s like me getting better every day, using the hose and taking advantage of it and helping the team out by getting yards and setting the tone. I just feel like that’s my responsibility every week.”

Sophomore Gavin Williams, who was Iowa’s No. 1 running back following spring practice, injured his ankle in the preseason. Since then, he’s been limited in practice and games. He didn’t record any statistics against Purdue on Saturday and has only accumulated 106 rushing yards this season.

Leshon Williams, the second-string running back, has also seen limited action. He’s registered 312 yards in eight games, including 2 yards on one attempt against Purdue. Head coach Kirk Ferentz said his running back room has been impacted by injuries this week, but he didn’t specify if Leshon Williams is injured.

“We were a little bit depleted over the course of the week, but Kaleb was not [injured], fortunately,” Kirk Ferentz said. “I’m just happy for him, and as I’ve said all along, he’s a great young guy. He’s got a great personality, great to work with, great attitude.

“He’s still figuring it out as a back, but he’s doing pretty good today for not knowing what he’s doing sometimes. But a lot of positive things and really excited about him and his future,”

Johnson is just nine games into his college football career, but he doesn’t carry himself as a freshman on the field, safety Kaevon Merriweather said.

Off the field, however, is a different story.

“For a freshman, [his confidence] is incredible,” Merriweather said. “To have the confidence, especially as a running back, to go in there and play Big Ten football … sometimes [you forget he’s a freshman] until you get off the field and start talking to him, then you’re like, ‘Yeah, you’re a freshman.’”