The Tigers used 19 hits to overcome a 3-1 Arkansas lead and broke open a 6-3 game with seven runs in the eighth inning.
After shutting out Arkansas in the first two games, LSU (30-15, 12-8 SEC) weathered 13 hits from the Razorbacks on Sunday to win the 18th game out of its last 21 contests.
Arkansas (23-18, 7-11) suffered its fourth straight loss, while LSU won its ninth home game in a row in front of an announced crowd of 4,415.
Every Tiger in the starting lineup recorded a hit and an RBI in the game, and six hitters had multiple hit games.
J.C Holt led LSU with a 4-for-6 performance, including a triple and three runs scored, to increase his average to .333 for the season.
"We feel so much better when we have that arrogance about us," said Holt.
The Tigers head into next weekend's SEC series at Tennessee a half-game behind Florida for fourth place in the league.
"They're starting to hear us coming," Holt said of the conference competition. "We're playing well and people can feel the pressure."
LSU scored its first run in the first inning on a sacrifice fly from Sean Barker. His fly to deep center brought in Holt, who led off with a single and moved to third on one-out Wally Pontiff's base hit.
Arkansas tied the game in its next at-bat with a solo homer from Michael Conner. It was the 12th homer of the year for the senior centerfielder.
The Razorbacks took a 2-1 lead in the third inning when Nick Pitts hit a grounder to short. Aaron Hill's only play was to get the out at first, allowing Scott Hode to score from third. Arkansas had put runners on the corners with one out to set up the scoring play.
Conner made the score 3-1 for Arkansas after leading off the fourth with a walk and advancing to second on a passed ball charged to Chris Phillips. With one out, Conner stole third and scored on Cody Clark's two-out single to left field.
Holt scored again in the bottom of the fifth for LSU after he launched a one-out triple to right center. Hill scored him with a single to make the score 3-2, and Pontiff drew a walk that ended the day for Arkansas starting pitcher Gary Hogan Jr.
Scott Woods took over on the mound and got the Razorbacks out of the jam by striking out Barker and getting Matt Heath to fly out to center.
Starting pitcher Bo Pettit lasted through one out in the sixth for LSU, leaving after giving up three Arkansas runs on nine hits with six strikeouts. He left runners on first and second for Jake Tompkins, who struck out Clark and got Hode to hit into an inning-ending force out at third.
"It took us until the seventh inning to get it going," said LSU coach Smoke Laval. "Bo really struggled but kept us in there. There's a difference. You can struggle and not have the game blow wide open."
The Tigers got to Woods (L, 5-1) in the sixth inning with three base hits, the third coming from Phillips to score Blake Gill and tie the game. The Razorbacks chose to put Scott Roehl in at pitcher after Phillips hit, but he surrendered the lead on a bases-loaded walk to Pontiff. The go-ahead run belonged to Woods, and Roehl contained the damage by getting Barker to fly to right for the third out.
Designated hitter Dustin Hahn extended LSU's lead to 6-3 in the seventh inning with a two-run, wind-aided homer to the gap in right – his second long ball of the season.
Tompkins (W, 3-0) faltered slightly in the eighth inning, loading the bases with a single and two walks with one out. But he recovered to get Kirk McConnell and Scott Bridges to fly out to end the inning.
"We pitched outstanding the whole weekend," said Pontiff. "We knew we couldn't hold (Arkansas) forever, but we came out with enthusiasm and intensity and responded well."
In the breakout eighth inning, the Tigers touched reliever Arkansas Layne Berry for four runs on three hits and scored three more on four hits against Josh Merryman. David Raymer brought in two with his double to center field to put LSU ahead 13-3.
Arkansas scored twice in the ninth for the final score.