Justin Meier replaced Billy Sadler and hit a batter with his first pitch but retired the next two to preserve the LSU's win.
It is the first time that LSU (18-9-1, 7-1-1 Southeastern Conference) has won a series against Alabama after losing the first game, and the win keeps the Tigers within a half-game of the overall SEC lead.
Mississippi State held on to first place with a an 8-4 win at Ole Miss, giving the Bulldogs a sweep of the rival Rebels. Auburn, who entered Sunday's action tied for the SEC lead, is a game out of first place after losing 7-6 to Georgia. It was the first SEC win of the season for the Bulldogs, who scored four runs in the bottom of the ninth in their comeback.
Clay Harris led LSU at the plate in a game with a line score that harkened back to the Gorilla Ball days. The Slidell sophomore had two home runs and was one of three Tigers with 3-for-5 performances.
"Today was a big day for hitters," said Harris. "If you got it up in the air today, it was going to go out of here. This game showed no lead is big enough, especially in college baseball."
After watching Alabama jump out to a lead in the first inning of the first two games of the series, LSU got the jump start in its first at-bat Sunday. Blake Gill's double into left field scored Aaron Hill and J.C. Holt.
It gave Gill seven RBIs for the series and continued LSU's success with two outs. For the series, the Tigers scored 15 runs with two outs.
LSU starting pitcher Nate Bumstead (3-1) gave Alabama a run in the bottom of the first after he walked Allen Rice and brought him home with three wild pitches.
Adam Pavkovich tied the game, 2-2, in the third inning with a sacrifice fly that scored Travis Garner, who led off the inning with a double.
Harris quickly put LSU back ahead with a home run to left center lead off the fourth.
His second homer came in the fifth and was the second LSU long ball of the inning. Naccarata provided a two-run shot to right field, and Harris delivered a one-out blast to left field to put the Tigers ahead 6-2.
Naccarata's homer ended the afternoon for Alabama starter Allen Ponder (2-2), who was pulled after serving up five runs on eight hits.
Brian Reed replaced Ponder and got Gill to ground out before Harris hit his second homer. The Tigers followed with three more singles, the third from Matt Liuzza to give LSU a 7-2 lead.
The Tigers continued their two-out damage in the sixth by adding two more runs on a Patterson single and another pair on Jon Zeringue's third homer of the series.
Zeringue's shot beyond the left field fence was his sixth home run of the season and fifth over the last six games.
With LSU leading 11-2, Alabama refused to roll over in the bottom of the seventh. Pavkovich singled in two runs and two more scored on Beau Hearod's towering home run to left field. It was the second round-tripper of the series for Hearod, a Jennings, La., native.
Jason Determann replaced Bumstead to begin the eighth inning and retired the Alabama side in order. Bumstead left having allowed six runs on eight hits with two walks and six strikeouts.
Sadler took the mound for LSU in the ninth and issued a walk and two hits to load the bases with one out. Hearod, the SEC's best power-hitter, came up next and got a grounder between Harris' legs at first and into the right field corner to score two runs.
A rattled Sadler walked Zac Welch to load the bases again, and a wild pitch allowed everyone to move up a base and made the score 11-9.
Sadler then walked the potential go-ahead run, LSU transfer Nathan Meiners, on four straight pitches to put three runners on base again. An irate Sadler argued that time had been called before he threw the fourth ball, but he was removed from the game for Meier.
The first pitch from Meier hit Al Hecklinski to draw the Tide to within a single run.
Grant Redding took a third strike for the second out, putting the game in the hands of catcher Bobby Burns.
Swinging on the first pitch from Meier, Burns popped up behind the plate where Liuzza made the catch to end the game and give Meier his first save of the season.
"We want to be up by four or more in case of a grand slam," said LSU head coach Smoke Laval. "Thank goodness it was five runs."
LSU totaled 17 hits in the game and has seen a big jump in its power numbers over the last week. The Tigers have hit 14 home runs in their last seven games and now have 33 for the season.