AUBURN, Ala. -- Les Miles said he can use a hard-fought win over Auburn as "a tremendous lesson" for an LSU team more accustomed to lopsided victories.
Lesson No. 1: Defense still wins in the Southeastern Conference.
Sam Montgomery and the LSU defense delivered a first-quarter safety and shut out Auburn in the second half to give the second-ranked Tigers a 12-10 victory Saturday night.
Auburn led 10-9 at halftime but finished with only 183 yards -- 86 rushing and 97 passing.
"We were tested and we answered the call," Miles said.
A fumbled punt return by Auburn's Quan Bray set up Drew Alleman's 30-yard field goal late in the third quarter that gave LSU (4-0, 1-0 SEC) a 12-10 lead. Alleman missed a 34-yarder with 39 seconds remaining.
Auburn (1-3, 0-2 SEC) managed only one first down after Alleman's miss. Kiehl Frazier's final pass was intercepted by Tharold Simon as the game ended.
"We didn't finish," Auburn coach Gene Chizik said. "There will be a day when we will. We will continue to grind and work until we can."
Montgomery led the defense with a career-high 3 1/2 tackles for losses and challenged the team at halftime to "play like I play."
"I believe that during times of adversity, the older, veteran players have to get everybody's heads on straight to lead and go and play for the victory," said Montgomery, a junior.
Montgomery called the close win "a shock to our system."
"It was some of the younger guys' first time on the road and not knowing what to expect," Montgomery said. "A couple of veteran guys hadn't been in that situation in a long time. It was really a shock to our whole program, but we adjusted. We stuck our backs up."
LSU's only touchdown came on a 1-yard run by Michael Ford in the first quarter.
Miles called his team's performance "not perfect."
"It's something we'll certainly be able to teach from in a very aggressive manner," Miles said. "There's work to do, but we'll take a victory on the road at Auburn."
The win gave LSU its sixth straight 4-0 start and extended its streak of regular-season wins to 17, the longest in the nation.
LSU's Zach Mettenberger had two first-half fumbles but threw a 33-yard pass to running back Spencer Ware on a key third down late in the game.
"That pretty much sealed the game for the most part, or at least it got it down to the wire," Chizik said.
Montgomery tackled Tre Mason in the end zone midway through the first quarter and Ford's 1-yard TD run four minutes later made it 9-0 LSU.
Onterrio McCalebb scored Auburn's touchdown on 4-yard run on the last play of the first quarter to make it 9-7 and from there it was nothing but field goals and defense.
McCalebb was held to 24 yards on 11 carries.
LSU outscored its first three opponents 145-31, but its conference opener was a much bigger challenge. LSU was favored by almost three touchdowns. The Tigers ran for 182 yards -- almost 100 yards below its SEC-leading average.
"I'm very proud of the defensive strides we made," Chizik said. "Do we have a long way to go? Absolutely."
Ware, who was only fifth on the team with 38 yards rushing through three games, led LSU with 16 carries for 90 yards. Kenny Hilliard had 10 carries for 40 yards.
LSU held the ball for 11 plays on its opening drive, moving to the Auburn 2 before Auburn defensive tackle Jeffrey Whitaker recovered Mettenberger's fumbled snap. LSU center P.J. Lonergan left with a leg injury earlier in the series, and the fumble came on the snap from backup center Elliott Porter.
"I made a couple of mistakes early on, but I think this win really showed the character of this team," said Mettenberger, who completed 15 of 26 passes for 169 yards.
"I think I handled the pressure well."
Lonergan returned on LSU's next possession.
Auburn had a false-start penalty on its first play after the turnover, pushing the Tigers back to their 1, setting up Montgomery's tackle of Mason for the safety.
LSU appeared to be in total control when Ford's scoring run capped a 59-yard drive.
Mettenberger's second lost fumble, caused by Corey Lemonier's hit, shifted the momentum to Auburn. Angelo Blackson recovered for Auburn at the LSU 26. Mason's 26-yard run set up McCalebb's 4-yard touchdown run.
Cody Parkey's 40-yard field goal late in the half gave Auburn the 10-9 halftime lead.
"We fought our tails off," said Auburn tight end Philip Lutzenkirchen, who had five catches for 29 yards. "Defense played really well. Offense didn't."
Frazier completed 13 of 22 passes for 97 yards with two interceptions.
Chizik said he had "a very heavy heart" after learning a student assistant died. An Auburn spokesman said the student was Joe Bagwell, 23, of Huntsville, Ala. Bagwell was in his first season as a student coach after working as a student trainer in 2011.
Chizik said the death was not expected. He provided no further details.
"It's very tragic, and our thoughts and prayers go out to his family," Chizik said.