This was worse.

LSU’s defensive performance in the season opener was historically bad.

But the one the No. 17 and soon-to-be-unranked Tigers gave in a 45-41 loss at Missouri on Saturday was worse.

Mississippi State’s K.J. Costello passed for an SEC-record 623 yards and 5 touchdowns in a 44-34 Bulldogs victory in Tiger Stadium two weeks ago.

This was worse.

Connor Bazelak threw 34 passes at the LSU defense. Five were incomplete, 4 went for touchdowns. He didn’t match Costello’s passing yards, but he still had 406, and unlike Costello he had to share the football with a 100-yard rusher.

LSU couldn’t stop the run. They couldn’t stop the pass. Most of the time, they couldn’t even figure out where the football was.

The season opener was the first game under new defensive coordinator Bo Pelini. The Tigers were missing virtually every starter from last year’s defense. Star cornerback Derek Stingley Jr. missed the game after being hospitalized because of an illness less than 24 hours before kickoff.

None of that excused the 623 yards, but they were all relevant factors in the dismal performance.

This was worse.

Pelini had two weeks from that game to this one. In between, Stingley returned, and the defense took advantage of an outmanned Vanderbilt team to fix stuff and presumably build some confidence.

Then came Missouri.

The game was moved from Tiger Stadium to Columbia in the middle of the week because Hurricane Delta was a threat to the Baton Rouge area.

The LSU defense looked like it still was primed to kick off at 8 p.m. at Tiger Stadium, because it clearly wasn’t ready to play at 11 a.m. at Faurot Field. Or any other time during the next 3 1/2 hours.

LSU were fooled by trick plays. They were fooled by misdirection. They left receivers uncovered. They missed tackles. They didn’t pressure the passer. They didn’t cover receivers with any regularity.

They did everything wrong except recover a couple of fumbles, which in the end didn’t do anything except probably keep Missouri from finishing with 50-some points.

“It was all on the defense,” LSU coach Ed Orgeron said afterward. “We’ve got to get it fixed.”

But there’s so much to be fixed. And so little time before going to the Swamp to face Kyle Trask, Dan Mullen and a really good Florida offense.

The shortcoming that occurred most frequently Saturday was mental breakdowns.

Numerous times after the Tigers allowed a big gainer and/or touchdown, multiple defensive players looked and pointed at one another.

Someone thought someone else was supposed to do something that neither one did.

That happened a lot.

“Too many busts,” Orgeron said.

Yeah, it’s a young defense playing a new scheme under a new coordinator.

The season opener was Mississippi State’s first under first-year coach Mike Leach. It was the first game in the offense for Costello, who transferred from Stanford.

Saturday marked Bazelak’s sixth career game. It was Missouri’s third game running first-year coach Eliah Drinkwitz’s offense, which produced a total of 31 points in losses to Alabama and Tennessee to start the season.

It’s early in the season for everybody. COVID-19 has complicated things for everybody. Everybody is going through some sort of transition.

Mississippi State’s offense knew what it was doing. LSU’s defense didn’t.

Missouri’s offense knew what it was doing. LSU’s defense didn’t.

The LSU defense has been thoroughly befuddled after two months of practice.

The Florida offense is easily capable of outperforming each of LSU’s first three opponents.

“It’s just not LSU defense,” Orgeron said. “We gotta get better. We’ve got to be more physical. We’ve got to fill our gaps.

“They got us out of our gaps. We couldn’t stop the run game. We couldn’t stop the play-action game and then, we bit up on the run, (and) we had guys wide down the field.”

LSU had some problems on defense last season even as it went 15-0 and won the CFP championship.

There were concerning performances against Texas, Alabama and Ole Miss along the way. But things got straightened out well enough to win the title, and for former coordinator Dave Aranda to be hired as Baylor’s head coach.

In came Pelini, who was LSU’s coordinator when the Tigers last won a national championship after the 2007 season.

Pelini’s scheme is supposed to be simpler than Aranda’s was.

But it doesn’t seem that way after watching all the confusion and missed assignments.

“I love Bo,” Orgeron said. “I think Bo’s going to be a great defensive coordinator. … But we have to coach better.”

If they don’t, it’s going to get even worse.