The LSU defense learned from a second-quarter lapse against Alabama-Birmingham on Saturday.

The Tigers got off to a dominating start, allowing just one first down on the Blazers’ three first-quarter possessions as they built a 21-0 lead by the end of the period.

UAB fumbled on its first play of the second quarter, and three plays later, the lead was 28-0.

Then a lot changed.

During the second quarter, the Blazers scored all 17 of their points and 183 of their 296 total yards (61.8 percent).

“We had shut them out in the first quarter, and it was three-and-out and three-and-out,” linebacker D.J. Welter said. “Then I guess we sat back on our heels a little, thinking, we’ve got this.”

The Tigers did, in fact, have their second victory in as many games as they were never seriously threatened in a 56-17 victory. But that second quarter livened up the locker room at halftime.

Coach Les Miles said defensive coordinator John Chavis came down from the press box to get his point across to the defense.

“We got him in at halftime, and the adjustments were just more emphatically put,” Miles said. “And I think our defense understood what to do and came out in the second half and held our opponents scoreless.”

The closest UAB got was 35-17 at halftime, thanks in part to Jamarcus Nelson getting behind cornerback Jalen Mills and safety Corey Thompson being too late getting over to prevent a 41-yard touchdown from Austin Brown.

“We felt like we may have gotten a little too comfortable (in the second quarter),” Mills said. “Once halftime was over with and we said what we had to say in the locker room we came out and did what we usually do and that’s dominate.”

Tigers emphasize tackling

One of the defense’s problems was missed tackles.

Miles said he didn’t care to recall just how many the Tigers had because it was much more than normal.

“We talk about missed tackles all the time,” Miles said. “It’s something that the defense really cannot give up. We look at personnel, and we look at how they respond to a missed tackle in that series.

“We’re certainly coaching it aggressively, and we would expect that we would reduce those, or reduce the playing time of those guys that have those missed tackles, one or the other.”

Linebacker Lamin Barrow said that at least some of the missed tackles could be blamed on defenders being “too anxious.”

“When you over-pursue, a lot of times you don’t take the right angle,” Barrow said. “You get to the ball so fast you give the runner an opportunity to cut back. We’re known for our big hits, and sometimes you miss when you try to take big shots.”

Jennings’ snaps on rise

Miles said ideally he’d like to get freshman quarterback Anthony Jennings about 15 snaps in Saturday’s game.

Jennings played one snap in the opener against TCU and 11 against UAB last week, completing his only pass for 11 yards and mishandling a shotgun snap.

“I think he understands what he needs to do,” Miles said. “I think he’s improving, he’s doing all the things off the field that he needs to do. I’d have to say that as a true freshman in Tiger Stadium for your first snaps, I think he acted just like he was supposed to.”

Alleva apologizes for inconvenience

Tigers Athletic Director Joe Alleva wrote a letter of apology to LSU students who were inconvenienced as they tried to enter Tiger Stadium for Saturday’s game.

A new entrance plan created lengthy delays entering the stadium. And in some cases, student IDs or tickets were not scanned in order to facilitate the crowd’s entrance. Students who purchase tickets to and attend regular-season games receive bonus points that can get them priority positioning for other purchases such as bowl tickets.

“Let me apologize for your experience entering Tiger Stadium this past weekend,” Alleva wrote in the letter, which was posted on the university’s website. “This year, we tried to make entering the student gates easier and more efficient for you — the student body — but unfortunately the plan did not work as expected. … It was a mistake.”

Alleva went on to assure the students that “anyone with a student ticket on their account will get a full credit for attending the game.” He added that “we have met with representatives of Student Government and are working with all parties to rectify the situation for this weekend.”

Slip of the tongue

For the second consecutive week, the Tigers are playing a team coached by someone familiar with them as an Arkansas assistant. Second-year UAB coach Garrick McGee was a Razorbacks offensive assistant for four years before joining the Blazers.

First-year Kent State coach Paul Haynes was defensive coordinator and secondary coach with the Razorbacks last season after a seven-year stint as an assistant at Ohio State.

Miles, a Michigan grad who generally won’t acknowledge his alma mater’s archrival by name, mentioned Haynes’ background with the Buckeyes when previewing this week’s game.

When it was pointed out to Miles that he had actually spoken the words “Ohio State,” he replied, “It was an accident.”