The LSU football team has lost its first starter of the season to injury, and it came at a position group that has struggled in the past two games.

Junior free safety Todd Harris is out for the year, LSU coach Ed Orgeron said Monday, lost because of an apparent right knee injury he suffered in the first quarter of the Tigers' 65-14 win over Northwestern State on Saturday.

Orgeron called the injury "an unfortunate accident" in which Harris "just landed on the ground wrong." Orgeron said Harris will redshirt this season.

Harris got caught up with a Demons receiver while defending a deep pass near the end zone, a play in which he was flagged for pass interference. The LSU athletic trainers helped Harris off the field, and he was later seen on crutches with an ice pack on his right knee.

The 5-foot-11, 190-pound Plaquemine High graduate has been the main safety used for deep coverage in LSU defensive coordinator Dave Aranda's scheme, which often uses three safeties at a time.

Grant Delpit, a unanimous All-American, plays strong safety, and junior JaCoby Stevens plays Aranda's "quarters" safety position, which is a safety/linebacker hybrid who plays at the edge of the line of scrimmage.

A constant rotation occurs in the LSU secondary during a game. It includes junior Kary Vincent, who subs in at nickel safety to cover opposing team's slot receivers.

The loss of Harris forces Aranda to alter his rotation, which may mean shifting defensive backs to different positions within the system.

It's unclear how exactly the secondary rotation will work when No. 4 LSU (3-0) plays at Vanderbilt (0-2) at 11 a.m. Saturday — the Tigers "haven't really discussed it yet," Stevens said. But Orgeron said Monday that Stevens "is going to play back there" in place of Harris.

"It's devastating," Stevens said of Harris' injury. "When somebody, one of your hardest workers on the team, one of the greatest teammates you've ever had, goes out with a season-ending injury, it sucks. I pray for him and I wish the best for him."

The 6-foot-1, 228-pound Stevens started at free safety in the last four games of the 2018 season in place of injured former free safety John Battle. It was "a good experience," Stevens said, that will help him "try and pick up where we left off."

After those starts, Stevens knew he had to get better covering the post in coverage — a deep route in which receivers angle toward the middle of the field, toward the goal post. He worked throughout the summer on his footwork and loosening his hips up.

The loss of Harris comes at a juncture in which the secondary is in need of improvement.

LSU is tied 69th nationally with 221.7 yards passing allowed per game. The Tigers surrendered 409 yards passing in a 45-38 win over then-No. 9 Texas, and FCS-level Northwestern State converted enough throws against LSU's zone defense to force Orgeron to switch to man-to-man when the Tigers led just 24-14 at halftime.

Can't see video below? Click here.

Northwestern State quarterback Shelton Eppler threw two touchdown passes against LSU, taking advantage of busted coverage on each score.

Orgeron said part of the problem was LSU's inability to create an effective pass rush against the Demons, an issue that was exacerbated by the absence of starting inside linebacker Michael Divinity (coach's decision), defensive ends Rashard Lawrence and Glen Logan (injuries) and outside linebacker K'Lavon Chaisson (injury).

Divinity will play against Vanderbilt, Orgeron said. Chaisson is "questionable," and Lawrence and Logan will miss the game with no timetable for recovery.

Unless the pass rush improves in those players' absences, the secondary will be facing similar circumstances in which they have to cover receivers longer than they'd prefer.

Orgeron can draw on recent experience on what that can mean: LSU ranked 32nd nationally with 34 sacks in 2018, which included five games in which the Tigers recorded one sack or none.

"The pass rush will cost us," Orgeron said. "We're experimenting with different things. We did a better job of mixing in our blitzes. We're going to have to blitz. We're not ready to use the four-man rush now with the guys that we have. We will use it, but how effective we can be, we have to get better at it."

Meanwhile, Stevens said the secondary has studied its issues with zone coverage from the Northwestern State game, and part of the solution comes from "just staying on our keys."

"We just can't get caught up in the backfield," Stevens said. "If the running back goes out a certain way and the tight end goes out a certain way, we need to pass that off. Some things like that. And if we do go off, we need to learn how to get in a hole and play off the quarterback. There's a lot of things that we need to do."

Email Brooks Kubena at