Shortstop Aaron Hill broke 1-1 tie in the fourth inning with an RBI double and later added a two-run homer an inning later. He matched his three RBIs with three runs scored.
LSU's offense was more than enough to bolster the second straight strong pitching performance from Bo Pettit. The senior threw six innings and improved to 2-0 by allowing one run on five hits with nine strikeouts and one walk.
It was the second succesful outing for Pettit (2-0), who missed the early portion of the Tigers' schedule recovering from a bout with the flu.
"I felt good out there," said Pettit. "I feel like I'm back into good pitching shape."
Greg Smith replaced Pettit on the mound and kept Winthrop hitless over the final three innings, striking out four Eagles for his first save of the season.
"He really got in on some left-handers and I liked that," said LSU coach Smoke Laval. "That impressed me."
Hill's double in the fourth hugged the third base line and brought in Ivan Naccarata, and Hill later scored on a Harris groundout to the shortstop.
LSU piled on three more runs in the fifth with an RBI single from Quinn Stewart. Stewart was picked off at first by pitcher Chris Carter, but Naccarata walked and scored on Hill's home run into the left field bleachers. It was his second homer of the season
"He (Carter) just left a curveball up, and I got a good swing on it," said Hill.
Ryan Patterson added two more runs for LSU in the sixth with a double down the third base line that scored Sprowl and Weaver.
Sprowl had extended his hitting streak to seven games with a double in the fourth inning and had an RBI in the seventh with a bases-loaded sacrifice to center field.
Naccarata provided the last two LSU runs in the eighth with his second home run of the year. The junior import from Canada blasted a two-run shot that sailed over the scoreboard in right field and onto Nicholson Avenue.
"In a previous at bat the pitcher had given me change-ups outside, curveballs outside, and then busted me inside with a fastball," said Naccarata. "It was the same count, and I thought he'd try to throw me inside and I just got the good end of the bat on it."
Naccarata extended his team-best hitting streak to 13 games with a single in the first inning.