Iowa football has several freshmen making impressions. Here's an update on their progress.

It didn't take long for Aaron Graves to experience his "welcome to college football" moment. 

The highly touted defensive lineman from Southeast Valley arrived on campus in June. He quickly found that the pace of a Power 5 program's routine is a large step up from high school. 

"The intensity and the speed that we do everything is so much different than anything I've ever been a part of," Graves said. "Everything is just super up-tempo. If they tell you something once, they expect you to have it locked in for forever and if you mess up on it, they'll certainly get on you. But it's for the best." 

Freshman running backs Kaleb Johnson and Jaziun Patterson recall a different type of moment: early collisions in fall camp with veterans Kaevon Merriweather and Lukas Van Ness that served as a "wake up." They're a natural part of any incoming freshman's journey, but the ability to learn and adjust quickly can separate players early on. 

"You definitely have to learn quick," Patterson said. "They give you chances, though. But you have to learn quick, especially if you want to play." 

Summer workouts leading into fall camp are the first chance for the majority of the freshman class to make impressions. Coach Kirk Ferentz has one goal in mind each year: See where each freshman is at entering the program and find a plan for everyone. 

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"Just kind of let them go to work, see what they can do and see how they ascend or don't ascend through the level of competition," Ferentz said. "If they can ascend and look like they can make a contribution, we're all for it. Other guys are a little bit more of a transitional period. What I tell guys in recruiting is it's more about your whole career, not just that first year." 

As fall camp nears a close, it appears that several freshmen could find roles this fall. Some — like defensive backs TJ Hall, Xavier Nwankpa and Drew Stevens — got a head start by enrolling early. Meanwhile, summer arrivals — like Graves, Johnson and Patterson — have proven to be quick learners. 

More:Leistikow: Unpacking the offseason progress for Iowa football quarterbacks Alex Padilla, Spencer Petras

Here's an update on several members of Iowa football's freshman class and where they stand in their position groups: 

Which adjustments have been hardest? 

Answers to this question vary. Graves noted the pace, Nwankpa pointed to the speed of the game. Of course there's an obvious physical adjustment, too. But nearly every Iowa freshman said learning the new playbook was the biggest challenge. 

The sheer size of it alone got Graves' attention when he first moved in. 

"(Defensive linemen) have a lot of calls, I'll put it like that," Graves said. "My playbook is probably like four inches tall and that's not even the biggest one. Some guys have like a six-inch (playbook), like a whole Bible. They're pretty big." 

Iowa had five early enrollees this year: Hall, Nwankpa, Stevens and defensive linemen Brian Allen and Caden Crawford. Those extra months on campus allowed them to learn the foundation in spring and process it through summer.

More:Iowa's Kyler Fisher, Jay Higgins carrying on Jestin Jacobs, Jack Campbell's linebacker legacy

Playbook intricacies vary by position. At running back, pass protection is tough to learn. For receivers such as Jacob Bostick, it's learning the route tree at multiple positions. In the secondary, Hall and Nwankpa had to adjust to a more complex way to receive calls than they had in high school. 

"It's not just a simple look to the sideline, one call," Hall said. "You got to look at the formation, get the play call see what you got to do within the play." 

Hall also pointed to body management as an adjustment. He enrolled in January around 166 pounds, and several months later he's up to 187 pounds. Bostick has added almost 10 pounds since arriving in June. 

Freshmen to watch on Iowa's offense

Offensively, there are several players who could crack the playing rotation. Injuries at both running back and wide receiver have opened the door for Bostick, Johnson and Patterson. 

Running back was a position of emphasis during last Saturday's Kids Day Scrimmage. Johnson and Patterson both impressed, combining for (unofficially) 21 carries and getting spot snaps with the first team. First-team reps for both players continued this week. Johnson scored a touchdown against the first-team defense during Tuesday's practice. 

More on running backs:What's the status of Iowa's running back room? Saturday's scrimmage provided some clarity

Sophomore and projected starter Gavin Williams is back at practice, so the Hawkeyes have their full compliment of running backs. Williams and fellow sophomore Leshon Williams are the favorites but both freshmen could be in line for spot carries if they continue their momentum. 

Iowa wide receiver Jacob Bostick is getting a big opportunity this spring practice as a result of injuries at his position.

Due to low numbers, Bostick is playing all three of Iowa's receiver positions during camp. Wide receivers coach Kelton Copeland said Bostick has shown promise over the last few practices, and he worked heavily with the team's second and third units on Saturday's scrimmage. When healthy, the Hawkeyes feel good about their top three options. But if injuries continue, the speedy Bostick could be counted on to play early. 

More:Iowa football's wide receivers are battling injuries. Here's an update midway through fall camp.

Another pass catcher to watch is tight end Addison Ostrenga. The Wisconsin native was a standout at Saturday's scrimmage, highlighted by a touchdown reception to end practice. He received the most reps after Sam LaPorta and Luke Lachey, indicating that Ostrenga is a serious contender for the No. 3 tight end position. Afterward, Ferentz confirmed that he's in the position battle. 

"He is right now," Ferentz said. "We'll see what he looks like in two weeks but getting injuries creates opportunity or lack of depth, either one. But (Addison's) handled things pretty well. He doesn't seem overwhelmed, so he's in the mix." 

Freshmen to watch on Iowa's defense 

Iowa defensive back Xavier Nwankpa, left, and running back Kaleb Johnson (2) are freshmen to watch this fall.

On defense, Iowa returns an impressive collection of talent, but there's opportunity up front and in the secondary. 

On the d-line, Graves is living up to his four-star recruiting hype. Ferentz said Graves "plays hard" on multiple occasions last weekend, and he was another standout performer at the scrimmage. 

"He's got the benefit of being a coach's kid," defensive line coach Kelvin Bell said. "His football knowledge is really good, but what's probably the most impressive are his instincts. He does some things that I haven't coached that he does naturally and that's good. Football comes natural to him." 

With nearly 10 contributors back last season, it wasn't out of the question early on that Graves could redshirt this season. As fall camp nears a close, there's no talk of redshirting and it appears that Graves will spend his freshman year as a rotational/depth piece. 

“Just the way he’s practicing, I think we’d be crazy to say we’re redshirting him. That’d be stupid on our part,” Ferentz said. “He’s got a lot to learn, but boy, his tempo … he belongs on the field with the older guys. He goes hard and makes them work. It makes us have better practices.”

Iowa running back Jaziun Patterson, left, gets tackled by defensive lineman Aaron Graves. Both freshmen had impressive debut scrimmages last Saturday.

The benefits of Hall and Nwankpa early enrolling were two-fold: They got a head start on learning the system and they arrived at a time when there were injuries in the secondary, allowing for more reps during spring practice. Both feel like they're much more comfortable in fall camp. 

Hall received some first-team reps during Iowa's final spring practice and is firmly among the second group of cornerbacks. During the scrimmage, Hall played heavily on Iowa's No. 2 defense while getting spot first-team reps. Iowa's top cornerbacks are set with Jermari Harris, Riley Moss and Terry Roberts, and there's also a chance Cooper DeJean plays come corner. After them, it seems like Hall and sophomore Brenden Deasfernandes are next in line. 

Iowa defensive back TJ Hall is a freshman who is competing for a role in the Hawkeyes' secondary this year.

Nwankpa's development plan has stayed consistent since he arrived: Learn safety first, then explore other positions like "Cash." Right now, one of his biggest adjustments is what's a hallmark of great Iowa free safeties: communicating on the field. 

"You have to be on the same page with the other safeties, corners and linebackers," Nwankpa said. "We all have to play the same defense at once, so having the whole defense together and not little spurts throughout practices and games is huge. 

"I did it a little bit in high school. But definitely coming to college there's a lot more calls, a lot more communication that you have to do. I had to grow up a little bit in that aspect but I think I'm making progress." 

Nwankpa made two signature plays that caused turnovers at the scrimmage: a tipped pass that led to a Karson Sharar pick-six and an interception of his own. He's working behind veterans Quin Schulte and Reggie Bracy right now, but Ferentz expects Nwankpa to continue pushing. 

"He had all summer to digest things," Ferentz said. "Now he's had (fall camp) practices under his belt. So my guess is we'll see him start to kind of gain ground with each and every day." 

Like some of his fellow freshmen, Nwankpa will be active on special teams this season. 

"Hopefully he helps us out on special teams," defensive coordinator Phil Parker said. "We’ll keep pushing him along a little bit every day. A little bit more reps here and there. He has a lot of potential, and I love his work ethic and I love his attitude.”

Where is Drew Stevens in Iowa's kicking competition? 

For more on Drew Stevens' status in Iowa's kicking competition and other special teams notes, click here

Kennington Lloyd Smith III covers Iowa Hawkeyes football and men's basketball for the Des Moines Register. You can connect with Kennington on Twitter @SkinnyKenny_ or email him at ksmith@gannett.com.