BATON ROUGE, La. -- A wide receiver who dreamed of running routes in Tiger Stadium as a 2014 recruit, Arkansas' Jared Cornelius made certain his home-state team would remember his name.

With his visiting Razorbacks clinging to a 10-point lead and the LSU offense beginning to hum, Cornelius, a Shreveport native who said he had an LSU offer, took an end-around 69 yards for a touchdown early in the fourth quarter - the third Arkansas touchdown of more than 50 yards on the night - to seal a 31-14 upset of No. 9 LSU on Saturday.

"They didn't really expect it. I got around the corner and saw there was nobody there and was like 'Oh my God,'" Cornelius said. "That did a lot for me. My dad played (at LSU) so it's in our family. Almost every kid grew up in Louisiana wanting to play for LSU."

Arkansas tailback Alex Collins, who battled a pulled muscle throughout the second half, rushed for 141 yards and two touchdowns to lead the Razorbacks' 299-yard performance on the ground.

Collins' 80-yard touchdown scamper gave the Hogs a quick 14-0 lead in the first quarter, while fellow tailback Kody Walker added 88 yards on 17 carries.

LSU quarterback Brandon Harris got another woeful performance from his offensive line - he was sacked five times by an Arkansas defensive front that entered the night with eight all season - but directed an impressive drive out of halftime to pull the Tigers within seven.

Harris hit wide receiver Travin Dural with a 25-yard pass to open the half before tailback Leonard Fournette - who had a long gain of 11 yards in the first half - broke a 12-yard run and a 13-yard touchdown scamper, bowling over would-be tacklers before scoring on the eighth play of the drive from the 2-yard line to pull LSU within 21-14.

The Arkansas defense stiffened afterward, forcing punts on the Tigers' next two drives and a turnover on downs just after Cornelius' run to put away any hope of a comeback in front of a restless, booing Tiger Stadium crowd.

"I thought we did a nice job of keeping (Harris) in the pocket, and if he did escape, he didn't escape for free yardage," Arkansas coach Bret Bielema said. "That was fun to watch."

Arkansas raced to a 21-0 lead thanks to Collins and quarterback Brandon Allen's effectiveness against a weary LSU secondary.

Collins, who lost a fumble on the Razorbacks' first series of the game, eclipsed 100 yards on his seventh carry of the game, which he took straight up the middle for an 80-yard TD on the second play of the second quarter to put the Razorbacks up 14-0 and leave the home crowd in a stunned silence.

"Alex responds to challenges, man," Bielema said. "He's a fighter. I love him to death, a kid who I think is giving us his all every day, every way. I jumped him pretty hard (after that fumble). I said 'Either get your mind right or we're going to find another option.'"

After the Collins fumble and a subsequent three-and-out from LSU's offense, Allen connected with receiver Dominique Reed on a wheel route. Reed did the rest, outrunning LSU's secondary for a 52-yard score and Arkansas' first points of the game.

Allen, who led the SEC in pass efficiency coming into the game, finished the first half 6-of-10 with completions to four different receivers.

Harris was wildly ineffective throughout much of the first half but found a groove on his final drive of the half, running the no-huddle offense and completing seven of his nine passes on a 92-yard drive.

A pass intended for Dural was deflected into fellow receiver Malachi Dupre's hands for a desperately needed score before the break.

After the second-worst home loss in his 11-year tenure, LSU coach Les Miles shook off any notion that the beatdown was a result of a hangover from last week's loss in Tuscaloosa, instead shouldering most of the blame.

"Anyone who would think this is a hangover from the Alabama game, that is absolutely untrue," Miles said. "I thought they fought. I thought they made mistakes. They wanted this game. ... This was mine. This was absolutely my fault."

NOTES: RB Alex Collins' 80-yard run tied former Razorback Darren McFadden's 2006 run for the longest that LSU allowed in Les Miles' 11 seasons. ... LSU LT Jerald Hawkins went down with an injury midway thorough the second quarter. He was replaced by KJ Malone, son of NBA legend Karl Malone. ... Fournette now has a touchdown in 11 straight games.