BATON ROUGE, La. -- No. 10 Auburn entered Saturday's showdown with unranked LSU having steamrolled its three previous SEC opponents by an average score of 48-16.

So when Auburn took a 20-0 lead on LSU two minutes into the second quarter, silencing the restless, sun-baked Tiger Stadium crowd, it looked like another rout in the making and a near certainty that it would break an 18-year losing streak in Baton Rouge.

Not so fast.

LSU's defense got off the deck to shut out Auburn in the final 32 minutes, D.J. Chark raced 75 yards with a punt for a touchdown early in the fourth quarter and freshman Connor Culp kicked field goals of 42 and 36 yards in the final 2:36 to lift LSU to a stunning 27-23 upset victory.

It was LSU's largest comeback victory in Tiger Stadium against an SEC opponent since 1949. LSU improved to 5-2 and 2-1 in the SEC and probably will move back into the Top 25.

"What a great win for our football team," LSU coach Ed Orgeron said. "Our football team is very resilient. We were down early in the first quarter, but I knew we were going to keep playing. We were going to keep fighting. No matter what happens, we're going to fight."

Auburn (5-2, 3-1) rolled up 290 yards and 13 first downs in taking a 23-14 halftime lead, but the LSU defense held Auburn to 64 yards and four first downs in the second half. Auburn converted only 3 of 14 third downs, including 1 of 8 in the second half.

Auburn scored on five of its first six possessions but was held scoreless on its final eight. In addition to taking the 20-point lead early in the second quarter, Auburn led 23-7 just two minutes before halftime.

Auburn quarterback Jarrett Stidham started on fire, going 6 of 8 for 145 yards and one touchdown in building a 17-0 first-quarter lead, but in the final 48 1/2 minutes he went just 3 of 18 for 20 yards.

Auburn called 17 consecutive running plays on first down in the second half, trying to milk the clock and get into decent position to keep the chains moving. Nothing worked.

"This is an extremely tough loss from the standpoint of getting off to a really good start," Auburn coach Gus Malzahn said. "This is the first time since I've been head coach where we couldn't hold on (to a big lead). That punt return broke our back. We were in pretty good shape up until that point."

LSU trailed 23-14 when Chark, who has had difficulty making decisions on which punts to return, took in Aidan Marshall's punt at the LSU 25. He made one man miss and then used his sprinter's speed to thread his way across field to the left sideline, where he outraced the Auburn punt coverage team.

"A lot of people doubted us early in the year," Chark said. "We listened to what a lot of people said, watched a lot of people turn on us."

Chark's return made it 23-21 with 14:33 left, and the LSU crowd came alive. LSU's special teams made another huge play with eight minutes left when receiver Russell Gage downed a punt inside the Auburn 5.

Auburn ran three plays for one yard, and Marshall had to punt from deep in his end zone to Chark at the Auburn 45.

LSU has had difficulty making field goals this season, but after moving the ball to the Auburn 25, Orgeron sent in Culp to attempt the go-ahead 42-yard field goal. The kick split the uprights and LSU led for good, 24-23, with 2:41 left.

"I believed he was going to make the play," Orgeron said of Culp, whose field goal last week helped defeat Florida 17-16 on the road. "He gained confidence from last week's kick."

Culp said this was the second game-winning field goal of his career. He kicked a 26-yarder with 19 seconds left to win a high school game.

"This one was bigger," he said. "Everything went black."

After stopping Auburn on its next possession, Culp hit a 36-yard field goal with 38 seconds left to make it 27-23.

Auburn kicker Daniel Carlson, who single-handedly beat LSU with six field goals in an 18-13 victory last season, made field goals of 46, 48 and 26 yards in the first half. Auburn also scored touchdowns on a 49-yard pass from Stidham to Will Hastings and a 4-yard run by Kerryon Johnson.

LSU got back in the game midway through the second quarter when Gage took a jet sweep around left end and raced 70 yards to the Auburn 7. LSU gambled on fourth-and-1 and it paid off with another jet sweep -- this one by receiver Stephen Sullivan -- to cut the deficit to 20-7.

Leading 23-7, Auburn made another defensive mistake on LSU's last possession of the first half. Cornerback Jamel Dean tried to jump an out route, but Chark caught the ball on the left sidelines and raced 37 yards to the Auburn 38.

Danny Etling made it 23-14 with a perfect 12-yard fade in the end zone to Gage, who laid out for the ball in the corner of the end zone.

NOTES: LSU honored the 2007 BCS National Championship team at halftime. Seventy players and head coach Les Miles got a standing ovation. That 2007 team went 12-2 and won the title with a 38-24 victory over Ohio State. ... With three more field goals in the first half, Auburn K Daniel Carlson is now 14 of 18 this year. He led all kickers last year in going 28-of-32. ... D.J. Chark became the first LSU player with two punt return touchdowns in the same season since Odell Beckham Jr. in 2012.