The spring has been spent breaking down which offenses (quarterbacks, running backs and wide receivers) will define the upcoming college football season, so it’s now time to look at what ultimately wins championships: the defenses.

The Georgia Bulldogs broke their 41-year title drought, then followed it up by becoming the first back-to-back champion in a decade, behind a stellar defense featuring a number of future NFL players. It comes as no surprise that the Bulldogs come in ranked No. 1 in ESPN’s top 10 defenses, but which teams, if any, can challenge the reigning champs defensively?

The SEC is known for its defense, but the Big Ten put just as many teams in our top 10, while the Pac-12 and Big 12 were nowhere to be found. See who our reporters think will be the top defensive units during the 2023 college football campaign.

Ten writers voted on a ballot with 10 points to the first-place defense down to one point for a 10th-place vote.

Points: 100 (10-of-10 first-place votes)

Defense has been Georgia’s calling card during the past two seasons that have resulted in back-to-back College Football Playoff national championships. Naturally, many will look to that side of the ball when trying to forecast the Bulldogs’ success for 2023, which is why people still have high expectations for their defense.

Despite losing key players to the NFL draft again this season in Jalen Carter, Kelee Ringo, Nolan Smith and Christopher Smith — as well as Bear Alexander to the transfer portal — Georgia’s defense is still stacked. The defensive line is anchored by veterans Zion Logue, Nazir Stackhouse, Tramel Walthour and Warren Brinson. Mykel Williams is coming off a minor foot surgery and will also be a big part of this group after leading the team in sacks last year. The Bulldogs are also hoping for development from the likes of Tyrion Ingram-Dawkins and Christen Miller.

Outside on the second level, you have Chaz Chambliss with the most experience, and hopes that Marvin Jones Jr. gets healthy. Inside will be strong for Georgia, where Smael Mondon Jr. and Jamon Dumas-Johnson (who were No. 1 and No. 2 on Georgia in tackles last season) return. Jalon Walker will also be a key player among the group, having worked both inside and outside. The secondary is led by familiar faces in Javon Bullard, Malaki Starks (third in tackles) and Kamari Lassiter.

In total, you’ve got a defense that once again is expected to compete to be the best in the country, and we didn’t even get to the Bulldogs’ highly rated recruits coming in this season. Given how Georgia has been recruiting, it’s hard not to see it this way not only this year, but for the foreseeable future. — Harry Lyles Jr.

​Points: 80

The Wolverines have reestablished their excellence on defense, overcoming key player and coaching losses after the 2021 season to once again finish in the top 10 nationally in points allowed (16.1) and yards per play allowed (4.7). They now have the continuity to build further as they aim for three straight Big Ten titles, another CFP appearance and a deeper postseason run. Second-year coordinator Jesse Minter, a Broyles Award finalist, will oversee a unit featuring an exciting mix of veterans, emerging young players and transfers, including linebacker Ernest Hausmann (Nebraska) and edge Josaiah Stewart (Coastal Carolina).

Michigan will miss Mazi Smith and Mike Morris up front but returns veterans Kris Jenkins, Mason Graham and Jaylen Harrell, plus sophomore Derrick Moore, an ESPN top-20 national recruit in 2022. If Harrell, Moore and others can spark the pass rush, the unit should be very solid across the board. Linebacker projects as a strength this season, as Michigan returns Junior Colson and Michael Barrett, who combined for 173 tackles and 5.5 sacks in 2022. Hausmann, who had 54 tackles as a freshman at Nebraska, is another nice addition.

Veteran defensive backs Rod Moore, Mike Sainristil, Makari Paige and R.J. Moten are back, and Michigan has high hopes for cornerback Will Johnson, another ESPN top-25 recruit in 2022, as well as spring standout Amorion Walker. Michigan’s CFP semifinal loss to TCU exposed some vulnerabilities, so there’s an obvious next step for the unit. The continuity with Minter and much of the personnel puts Michigan on track to be possibly an even better defense in 2023. — Adam Rittenberg

​Points: 74

Alabama’s defense is under new leadership with Pete Golding leaving to take the Ole Miss defensive coordinator’s job. Veteran Kevin Steele takes over as Alabama’s coordinator, which will be his third stint working under Nick Saban. Steele knows Saban’s defense and knows the SEC. He was a Broyles Award finalist at Auburn in 2017, when the Tigers beat the Crimson Tide and played in the SEC championship game. One of Steele’s priorities is generating more negative plays on defense and forcing opposing offenses into mistakes. Alabama finished 11th in the SEC a year ago with only 17 forced turnovers in 13 games.

Not that Alabama’s defense will necessarily go as outside linebacker Dallas Turner goes next season, but if he bounces back with the kind of season he’s capable of, the Crimson Tide could go from very good to elite. Turner finished with eight tackles for loss (four sacks) last season and will play an even more vital role this season with his All-American outside linebacker mate on the other side, Will Anderson Jr., off to the NFL. The interior of the Alabama defensive line will be led by 6-foot-5, 328-pound tackle Jaheim Oatis, who is in the best shape of his career and poised for a monster season. Redshirt senior tackle Justin Eboigbe is a candidate for comeback player of the year after missing all but four games last season with a neck injury.

The Crimson Tide had their problems in the secondary a year ago, but junior cornerback Kool-Aid McKinstry is back after showing up on some All-America teams in 2022. He has the skill set to emerge as one of college football’s premier cornerbacks. The player who caught everybody’s attention in the spring was freshman safety Caleb Downs, rated by ESPN as the No. 1 safety prospect and No. 11 player overall in the 2023 class. That’s good news for the Tide because their play at safety last season was shaky. — Chris Low

​Points: 60

Penn State’s defense was one of the best in the country last year, and it should be again with coordinator Manny Diaz returning for his second season. The Nittany Lions allowed just 18.2 points per game, which was the seventh fewest among all Power 5 teams.

The defensive line will be the strength of the group, particularly on the edge, where Chop Robinson and Adisa Isaac will be the stars. The staff also has high expectations for Dani Dennis-Sutton.

Diaz said the Nittany Lions will comfortably be able to play eight to 10 guys up front without a drop-off. While plenty of talent returns from last year’s defense, it lost some “incredible leadership” and “big-time personalities,” Diaz said. Cornerback Joey Porter Jr. and safety Ji’Ayir Brown, who was the Rose Bowl’s defensive MVP, have left some voids.

“I don’t see those same personalities,” Diaz said. “That will be a big question for us.”

Penn State’s defense excelled at shutting down opposing quarterbacks last year, pressuring opponents on 38.9% of their dropbacks — the highest in the FBS. Penn State’s defense forced two turnovers per game, tied for the third most among Power 5 teams.

“We made a step a year ago, and obviously we play in a heck of a division,” Diaz said. “And so to try to take that next step and get yourself playing in that final four, it’s the smallest of margins, and sometimes are the ones that are the hardest to see. I think the players are understanding how every little thing matters, and trying to look for the smallest types of improvement.” — Heather Dinich

​Points: 55

It is safe to say the Clemson defense was not up to its usual standard last season. The Tigers finished sixth (!) in the ACC in total defense — the first time in nine years they were not top two in the league. First-time coordinator Wes Goodwin had big shoes to fill in replacing Brent Venables. But it also did not help that Clemson had injuries to key players on its defensive line, including starter Bryan Bresee, and had difficulty stopping the pass with a secondary that gave up far too many big plays.

But there is reason for optimism headed into 2023. Clemson returns the best starting linebacker duo in the country in Jeremiah Trotter Jr. and Barrett Carter, who combined for 169 tackles in their first year as starters in 2022. They showed the type of big-play capability that Clemson generally gets at linebacker — with 24 tackles for loss and 12 sacks between them. There is depth and veteran leadership along the defensive front, too, with Tyler Davis, Xavier Thomas and Ruke Orhorhoro returning. True freshman Peter Woods earned raves during spring practice and is expected to be a big-time contributor.

The secondary also should be better, with Nate Wiggins and Andrew Mukuba returning and the addition of freshman Khalil Barnes. The spring game showcased the potential this defense has headed into the season. Going into Year 2 as the defensive playcaller should be a significant help for Goodwin as well. — Andrea Adelson

​Points: 41

No defense on this list bears a bigger burden than Iowa’s, which has overcome some baked-in recruiting challenges and its own offense to become a nationally elite unit. The team is 78-36 since 2014 and 51-23 since 2017, despite having an offense that ranks 91st and 93rd nationally in scoring over the same two spans. Even when Iowa’s offense plummeted to historic lows last season, the defense rose up, ranking No. 2 nationally in fewest points allowed (13.3 PPG) and sixth against the pass (169.5 YPG).

Since 2018, Iowa ranks second nationally behind Georgia in points allowed (16.1) and since 2017 leads the FBS in turnovers gained with 146. The Hawkeyes face some immediate challenges in 2023, having to replace NFL first-round draft picks Lukas Van Ness and Jack Campbell among others. But the group also brings back star power and experience, including cornerback Cooper DeJean (five interceptions in 2022) and defensive end Deontae Craig (6.5 sacks, 3 forced fumbles).

Craig joins veteran linemen Joe Evans, Noah Shannon and Logan Lee to form what should be one of the nation’s best fronts. Defensive coordinator Phil Parker’s secondaries have been consistently strong and often excellent, and DeJean will lead a group that includes veterans Quinn Schulte, Jermari Harris and Sebastian Castro, and an emerging young star in Xavier Nwankpa, an ESPN 300 recruit in 2022. Iowa has some holes to fill at linebacker, but the unit’s history under Parker suggests another top-10-type season, especially since the offense can’t get much worse. — Rittenberg

​Points: 34

Florida State has made significant progress on defense each year Mike Norvell has been head coach. Headed into 2023, the defense is expected to take an even bigger leap thanks to major contributors returning and yet another influx from the transfer portal.

Start with the players coming back. Defensive end Jared Verse could have gone into the NFL draft but decided to return to improve his already high draft stock. Verse was dominant when healthy last year, leading the Seminoles with 7.5 sacks and 14.5 tackles for loss in his first season on the FBS level. Coaches raved about his work ethic and improvement this spring, and he is a key force along what should be a strong defensive front. Fabien Lovett also returns on the interior, and so does Patrick Payton, the ACC Defensive Rookie of the Year in 2022. Payton might be the most improved player along that front. Florida State also added Western Michigan defensive tackle transfer Braden Fiske to the rotation.

Among the transfers Florida State signed who should make an immediate impact is cornerback Fentrell Cypress II, a second-team All-ACC selection at Virginia a year ago. He should help a secondary that made strides, ranking No. 4 in the nation in pass defense. Florida State led the ACC in defense last season and ranked in the top 15 nationally, but it’s not hard to project this unit as one of the most dominant headed into 2013. — Adelson

​Points: 31

It always starts right up front with any defense, and getting back a healthy Maason Smith at tackle is a huge boost for an LSU unit that finished fifth in the SEC last season in scoring defense (22.5 points per game) and sixth in total defense (354.6 yards per game). Smith earned Freshman All-America honors in 2021, but tore his ACL in the opener last season against Florida State while celebrating a tackle. The 6-6, 310-pound Smith is a force in the middle of that defense, and Mekhi Wingo showed a year ago he was also capable of being a dominant interior defender. Throw in one of the best pass-rushers in the SEC, outside linebacker Harold Perkins Jr., and the Tigers will be a load for any opposing offensive line trying to block them. Perkins had 7.5 sacks and three forced fumbles as a freshman last season.

LSU will also benefit from having defensive coordinator Matt House and his staff back for another season. The continuity and carryover from 2022 should allow the Tigers to play even faster and more instinctively, and one of the keys will be how well several transfers fit on defense.

Linebacker Omar Speights transferred in from Oregon State, where he was a first-team All-Pac-12 selection last season. There are some question marks in the secondary, although veteran safety Greg Brooks Jr. is back. A number of transfers will get chances to win cornerback jobs. Among them: JK Johnson (Ohio State), Duce Chestnut (Syracuse), Denver Harris (Texas A&M) and Zy Alexander (Southeastern Louisiana). — Low

​Points: 29

Jimbo Fisher and Texas A&M hired former Ole Miss defensive coordinator D.J. Durkin to the same position back in January 2022 to replace Mike Elko, who left to become the head coach at Duke. Elko went 9-4 in 2022 while Durkin and the Aggies stumbled to a 5-7 finish — the team’s first losing record since 2009.

He returns a group in College Station that didn’t live up to expectations last season (they were 123rd in run defense) despite still finishing in the top 25 nationally in points allowed. The Aggies return talented veterans on the line in Fadil Diggs, McKinnley Jackson and Shemar Turner, as well as players from a historic 2022 defensive recruiting class that includes linemen Gabriel Brownlow-Dindy, Walter Nolen, LT Overton, and Shemar Stewart.

The Aggies had many departures via transfer behind the line. But Chris Russell Jr. and Edgerrin Cooper are back in the second level of the defense, where Cooper led the team in tackles for loss in 2022. In the secondary, Demani Richardson and Jardin Gilbert give A&M experience at safety, while North Carolina transfer Tony Grimes and Tyreek Chappell look to hold things down at corner after Antonio Johnson departed for the NFL.

There’s not a lack of talent by any means on this A&M defense. It’s a matter of putting together a complete product on the field. — Lyles Jr.

​Points: 12

First-year coach Luke Fickell already has proven defensive success in the Big Ten at the highest level, as he was Ohio State’s co-defensive coordinator and linebackers coach from 2005 to 2016. His defense was a major reason the Buckeyes won the 2014 national title.

Now he’s trying to replicate that success at Wisconsin with coordinator Mike Tressel — and they’ve got plenty of experience returning to start with.

Four of Wisconsin’s top five tacklers from 2022 return, as do 73% of last season’s total tackles. The center of the Badgers’ defense should be strong with the return of linebackers Maema Njongmeta and Jordan Turner, the team’s leading tacklers in 2022. Njongmeta had 95 tackles, 12.5 TFLs, 3.5 sacks and an interception.

Wisconsin will be looking for new pass-rushers to emerge after the departures of OLB Nick Herbig and NT Keeanu Benton, but the Badgers return six other defensive players who totaled more than three TFLs in 2022.

“Numbers-wise defensively, they had been pretty good, especially the last few years,” Fickell said. “So that’s where you’re like, ‘OK, if there are going to be adjustments, it’s going to be a little bit harder to make sure everybody’s on the same page defensively.’ But that’s the benefit of having a really smart group. It’s a really highly intelligent group of guys. It’s always been the history of it. By nature, the school breeds that, which gives you a chance when you have change.” — Dinich

Others receiving votes: Illinois (11), Air Force (7), Utah (7), NC State (4), Kentucky (3), Ohio State (1), Oregon State (1).