A new era of Illinois football has arrived.

Following another subpar campaign from Lovie Smith, athletic director Josh Whitman decided it was time to find a new leader for the program. There has been real optimism for the Fighting Illini following a 6-win campaign in 2019, but following it up with just a 2-6 record this past season wasn’t good enough.

Now, the task has been handed to Bret Bielema to get Illinois up and running as a legitimate B1G program. Getting to bowl games consistently and challenging for division titles is the goal in Champaign, but it’s not going to happen overnight. In his first season with the Illini, Bielema has some work to do.

Here are the five biggest holes Bielema will have to fill in his first season with Illinois.

Wide receiver: Brian Hightower replacing Josh Imatorbhebhe

What you need to know: Imatorbhebhe’s departure leaves a big void in the passing attack for Illinois. He was the team’s leading receiver for the past two seasons and he was as sure-handed as anyone in the B1G. Losing that kind of threat is going to be difficult to replace.

The good news is that Hightower might have an easier time transitioning into that No. 1 spot, assuming he can elevate his game as the primary target. Illinois has other another option with Jafar Armstrong transferring in from Notre Dame, but Hightower has the experience and chemistry with quarterback Brandon Peters. Last year, Hightower had 11 catches for 209 yards and 3 touchdowns. He can be that downfield threat the Illini need.

Still, Imatorbhebhe had explosive playmaking skills and the ability to beat defensive backs for jump balls. Hightower has that same ability with the 6-foot-3, 220-pound frame, but doing it on a regular basis as the top target could be challenging.

Offensive line: Alex Pihlstrom replacing Kendrick Green

What you need to know: Watching Green enter the NFL Draft might’ve been the biggest loss of the offseason for Illinois. He started in 33 consecutive games and showed the ability to play multiple positions on the offensive line. If Green would’ve returned, the Fighting Illini might’ve had arguably the best offensive line in the B1G West. Or at least one experienced enough to cause problems in 2021.

Instead, Bielema will (likely) turn to Alex Pihlstrom as the replacement up front. He appeared in all eight games for the Fighting Illini in 2020 and made two starts. He’s still a raw talent, but the new coaching staff should be able to mold him into a tough offensive lineman who complements a really strong group up front.

Losing Green was undoubtedly a big deal, but Illinois should still be in good shape on the offensive line this season. Philstrom being in the rotation should allow him to learn quickly as a starter.

Linebacker:  Calvin Hart Jr. replacing Jake Hansen

What you need to know: The loss of Hansen is probably the most significant defensive departure for the Fighting Illini in 2021. He truly embraced the style of “Lovie Ball,” and was a takeaway machine during his time in Champaign, accounting for 10 forced fumbles and 3 interceptions. He was also a sure tackle, piling up 243 stops over four seasons.

Hart comes to Illinois from NC State, where he served as a backup linebacker for the Wolfpack during the 2020 season. In 10 games, he made 18 tackles with 3 stops for loss, 2 forced fumbles and 2 sacks while playing in 10 games. With the linebacker corps depleted and inexperienced, he should be able to jump right into the mix and challenge for a starting job.

Replicating the kind of production Hansen had on the field, especially in the turnover department, is no easy task. This is going to be a big position to keep an eye on for the 2021 season.

Linebacker: Tarique Barnes replacing Milo Eifler

What you need to know: Eifler was another solid player for Illinois at the linebacker position, which is another reason why Bret Bielema has his hands full trying to replace this group in his first year in Champaign. Eifler wasn’t quite as productive as Hansen, but he still registered 13.5 tackles for loss and 3 sacks over the past two seasons for the Fighting Illini.

Barnes is one of the few linebackers at Illinois with some experience, playing in five games and making two starts in 2020. He did sustain  a leg injury that kept him out of three games, so his health could be a concern preparing or the upcoming year.

In five games, Barnes flashed plenty of potential. He was credited with 25 tackles, a sack, a fumble recovery for a touchdown and an interception. He has the ability to be a great linebacker with more reps.

Defensive back: Jartavius Martin replacing Nate Hobbs

What you need to know: Hobbs was a consistent player for the Illini in the secondary, with his best season coming in 2019 when he broke up 10 passes and collected an interception as the team reached bowl eligibility for the only time under Lovie Smith. He may not have been considered a “lock down defender” but he was still really good at keeping receivers in check.

Martin came on strong at the end of the season, making his first two career starts in the final two games of the 2020 season (Northwestern and Penn State). He finished the year with 38 tackles, 2 passes defended and a forced fumble. He’ll have to continue to improve in coverage and show that he’s capable of defending B1G wide receivers.

Illinois got consistency out of Hobbs in the secondary. That’s what it’ll need from Martin, as well.