With both National Signing Days now complete, college football coaches can start putting pieces in place and names on depth charts to get a better idea of what their teams will look like in the upcoming season.

Kirk Ferentz's Iowa Hawkeyes lost a couple of big-name contributors from the 2017 squad. Luckily, however, the Hawkeyes are welcoming in some new faces who could provide an immediate impact and help soften the blow of the loss of some of that star power.

Here are five Iowa newcomers to watch in 2018.

Daviyon Nixon, DT

The Iowa Western Community College transfer received a couple of offers this past fall — including one from Alabama. He remained loyal to the Hawkeyes throughout the recruiting process and could be a wild card in regard to the Big Ten West race. He's the kind of talent that can potentially change the entire look and identity of a defense. He's powerful and agile, able to stuff running lanes as well as he chases down quarterbacks with his rare athleticism. Iowa's front four was already going to be one of the better units in the conference. Nixon gives the Hawkeyes the potential to field one of the best defensive lines in the country.

Tyrone Tracy, ATH

Tracy might be the best athlete on Iowa's roster the moment he steps inside the locker room. He has the ability to line up at running back or receiver and cause a variety of matchup issues. Depending on how creative offensive coordinator Brian Ferentz wants to get, you could see an entire package installed around Tracy's skill set. Iowa doesn't get many guys at the skill positions who can do the things Tracy does. He could be an important piece of the puzzle for the Hawkeye offense in 2018. He'll also likely get looks as a kick returner.

Dillon Doyle, LB

Doyle enrolled in January and will get valuable time in the weight room and reps in the spring. He's a very athletic linebacker who closes quickly on ball carriers. Ideally he'd redshirt, but that may not be possible with some of the question marks the Hawkeyes have at the position. Youth and inexperience on the depth chart could work in Doyle's favor, as his talent could be enough to get him significant playing time.

Dallas Craddieth, DB

Craddieth is a grown man. He has a FBS-ready body right now and it would be a waste to redshirt him. He'll likely get significant reps at both safety positions throughout the year. Watching him on film, there are times when he plays like a linebacker, which will make him an asset to the Hawkeye defense against some of the better running teams on the 2018 slate. His is a name you'll hear a lot on special teams as well.

Jayden McDonald, LB

When it's all said and done, McDonald could very well end up being the gem of the 2018 recruiting class for the Hawkeyes. Iowa had to fight off the likes of Ole Miss and Kansas State to land him. Like Dillon Doyle, McDonald will have a realistic shot at competing for serious playing time right away. He has the kind of speed that Iowa does not currently have in its linebacking corps. If he can come into fall camp at or around 230 pounds, you should see him in the regular rotation when the season kicks off.

— Written by J.P. Scott, who is part of the Athlon Contributor Network. His work has appeared on SI.com, FoxSports.com, Yahoo!, SBNation and Bleacher Report. Follow him on Twitter @TheJPScott.