BATON ROUGE — Huddles on defense this week during practice have been a little less energetic this week because of the absence of Harold Perkins.

"I describe Perk as energy. Just straight energy," LSU freshman defensive tackle Ahmad Breaux said of Perkins.

When the LSU football star junior linebacker went down with a season-ending knee injury in the team's win over UCLA last Saturday, the defense's most gravitational source of energy was lost as well.

That may be the biggest hurdle the No. 13 Tigers (3-1) will have to overcome the remainder of the 2024 season with Perkins not being able to suit up with his teammates, arguably even moreso than the X's and O's. The team will get its first test run without its top defensive playmaker when it welcomes South Alabama (2-2) to Tiger Stadium Saturday night (6:45 p.m., SEC Network).

Filling several different roles and playing multiple positions for Blake Baker's defense, Perkins' leadership on and off the field have been admired by his teammates and coaches, especially in how he handled every curveball.

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"I wouldn't say he's like a big talker, but the way he goes about his thing," freshman safety Dashawn Spears said. "He showed leadership by just playing and showing what you got to do to be Harold Perkins."

For opponents, Perkins has been the focal point for getting their gameplans together. Knowing where Perkins was in the formation was a must and where he was dictated which direction teams would run plays in many instances. Without him out there, teams will be able to spend less time worrying about him and should divert to more plays, formations and personnel groups they feel most comfortable.

"He carries an immediate — you got to pay attention to him from an offensive standpoint. ... He can wreck your day," Tigers head coach Brian Kelly said. "You lose that piece right away. Our players clearly understand that in this game, you're going to get injuries. Harold was gifted enough to play a receiver both as a linebacker and a nickel. We don't have many of those guys hanging around."

Kelly told reporters Monday that freshman linebacker Xavier Atkins will be activated to bring on additional depth at linebacker. Structurally, LSU has options. Whit Weeks, Greg Penn and West Weeks would make up the linebacking corps should Baker and Kelly decide to run a 4-3.

If the matchup calls for more defensive backs and coverage, LSU has the capability to revert back to a 4-2-5 and play senior safety Major Burns at the Star position and bring him back closer to the line of scrimmage.

Spears said Perkins has already been in Atkins' ear, trying to get catch him as much up to speed as he can so the young player can contribute for the defense as quickly as possible. It's that kind of leadership that won't be on the field, on the sideline and in the huddle during games for the rest of the season for LSU's defense.

"We're definitely going to have to step up because he has become a very vocal leader this year," LSU linebacker Whit Weeks said. "He's the guy that's firing us up in the huddle and getting everything right. Now, we're going to have to rely on someone else to do that for us. I'm not worried about his leadership role because we've got a bunch of leaders on defense."

It's difficult, but there's belief amongst the unit.

"Just go back to the drawing board with the other linebackers and get them in the right way," Spears said. "We did lose Harold Perkins but we also have Whit Weeks, Greg Penn and the other linebackers that are really good as well. I think we'll be OK.

"We're sad we lost Perk. We lost a leader, we lost a great teammate," Breaux added. "We'll see what happens going forward but we got people that are going to step up and do their job and I trust my teammates.

"(Perkins) never had a down moment, he's never looked down to us. Every time you look over to him, he's up, he's ready to go. That's what I respect about him."

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Cory Diaz covers the LSU Tigers for The Daily Advertiser as part of the USA TODAY Network. Follow his Tigers coverage on Twitter: @ByCoryDiaz. Got questions regarding LSU athletics? Send them to Cory Diaz at bdiaz@gannett.com.

This article originally appeared on Lafayette Daily Advertiser: What will LSU football miss without Harold Perkins? What players said