LSU improved to 22-10 overall and 3-7 in SEC play while Tennessee dropped to 18-12 and 2-7. The teams will meet in Game 2 of the series at 3 p.m. CDT Saturday.
"We were more opportunistic tonight than we have been in recent games," said LSU coach Smoke Laval. "That was the key; we took advantage of opportunities and we had some consistency at the plate."
LSU grabbed a 4-0 lead in the third inning as the Tigers sent 10 men to the plate against Tennessee starter James Adkins (4-4).
Centerfielder Jarred Bogany provided a two-run double to highlight the uprising, which also included an RBI single by catcher Matt Liuzza and a bases-loaded walk issued by Adkins to third baseman Will Harris.
The Tigers extended the lead to 6-0 in the fifth as shortstop Michael Hollander delivered an RBI triple and Harris contributed a run-scoring single.
Stewart unloaded a three-run homer in the sixth – his 13th of the season -- to give the Tigers a 9-0 lead, and his solo homer in the ninth highlighted a three-run rally to account for the final margin.
Coleman – making just his second career SEC start – limited the Vols to two runs (one earned) on eight hits in eight innings with two walks and two strikeouts.
"Louis did a nice job of filling the zone with strikes and competing with every pitch," Laval said.
Adkins was charged with the loss as he allowed nine runs (eight earned) on nine hits in seven innings with five walks and five strikeouts.
LSU roars past Tennessee 12-2
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