The college football season is right around the corner, and it is going to be an exciting one in the Big Ten. The conference is loaded with good teams, and there are high expectations after back-to-back national championships. Michigan won it all in 2023, and Ohio State captured the crown last season. There should be a good amount of teams that are still alive and contending for a national championship at the end of the 2025 season, and it will be exciting to see if another team from this conference can pull it off.

In terms of contenders in the Big Ten, Ohio State, Penn State and Oregon are the teams that you can essentially write in to make the College Football Playoff. All three teams made it last year, and they are all expected to be among the best teams in the country this year as well. Michigan, Illinois, Indiana and USC are all teams to watch, too. The Hoosiers and Wolverines both have CFP experience, and they are hoping to make it again. USC and Illinois are looking for their first appearance.

All in all, there is a lot of talent in the Big Ten, and the conference prides itself in its physical style of play and bruising defense. The Big Ten has some of the best defenses in the country, and that comes with having some of the best secondary units in college football. Here are the top five units in the conference going into the 2025 season:

5. Michigan

Michigan Wolverines defensive back Rod Moore (9) celebrates after he makes an interception in the second half against the Ohio State Buckeyes at Michigan Stadium.
© Rick Osentoski-Imagn Images

The Michigan football team has had one of the best defenses in the country during the last four seasons, and elite secondary play is a big reason why. Even last year, the Wolverines had no pulse offensively, but the defense managed to win them eight games. This defense is expected to be loaded once again, and the secondary appears to be in good shape ahead of the 2025 season.

Getting Rod Moore back from injury will be massive for the Wolverines defensively. He missed all of 2024 after tearing his ACL, but he is back and ready to go. Jyaire Hill, who had a great season last year, is another player to watch for Michigan, and so is Arkansas transfer TJ Metcalf. The Wolverines are in good shape to have one of the best secondary units in the Big Ten.

4. Iowa

When you think of good defense in the Big Ten, you think of the Iowa football team. The Hawkeyes are a team that is always anchored by the D, and they have put up some successful seasons despite struggling mightily on offense for multiple years. You can always bank on Iowa to have one of the toughest, most physical defenses in the Big Ten, and that will once again be the case this season.

Iowa always has a strong secondary, and that will be no different this season. The Hawkeyes have a lot of returning talent coming back who had strong 2024 campaigns. Deshaun Lee, TJ Hall, Xavier Nwankpa and Koen Entringer have all been with the program for multiple years, and they have only gotten better throughout their careers. They all seem poised for big 2025 seasons.

3. Illinois

The Illinois football team has come of nowhere in recent years in terms of talent in the secondary as the program has produced a lot of NFL talent lately. It looks like that is going to continue in the near future as the Fighting Illini are going to have another very good secondary this season. Illinois has suprised a lot of people with their recent success, and the team is expected to be even better this season. It is an exciting time to be a Fighting Illini fan.

Led by guys like Matthew Bailey and Xavier Scott, there is a lot of good returning talent in this Illinois secondary. Bailey and Scott especially have eye-popping numbers as Bailey recorded 93 total tackles last year, and Scott had four interceptions. The Illinois defense is in great hands.

2. Penn State

The Penn State football team is going to be one of the best squads in the country next year, and the Nittany Lions are elite at every position. The secondary is no different. Penn State always has a bruising defense, and it is going to be one of the best in the conference once again. The Nittany Lions are a popular pick to win the Big Ten, and this defense is a big reason why.

Penn State has a lot of NFL talent in this secondary, and a couple of players to watch out for are Zakee Wheatley and AJ Harris. The two of them combined for nearly 150 tackles and four interceptions last season. Both are coming back with a ton of meaningful playing experience, and they should both have huge seasons once again.

1. Ohio State

The best secondary unit in the Big Ten belongs to the Ohio State football team, and there is one player in particular that makes it so strong. That player is Caleb Downs. Downs is a top-three player in college football, and he isn't even viewed as the best player on his team. That's how much talent the Buckeyes have. Wide receiver Jeremiah Smith has Downs beat, but he is still a phenomenal talent and is poised for a huge season with the Buckeyes.

Last season was Caleb Downs' first with Ohio State after transferring from Alabama, and it was a big one. He racked up 87 total tackles, six passes defended, two interceptions and half a sack. It was a sensational year, and Downs should be even better this season. The Buckeyes are going to be in the mix for the national championship once again.

The Big Ten is clearly very talented when it comes to secondary units. The conference always has a lot of good defenses in general, and this year will be no different. All of these teams have great talent in the secondary, and they have great talent at every defensive position group as well. Expect these five squads to play some of the best D in the Big Ten.