Colby May had three hits including a double, and Chase Davidson and Bryce Massanari had two hits apiece. Massanari and Lewis both homered as the Bulldogs (20-3, 5-2 SEC) won their fifth straight league game.
Trevor Holder (5-1) sat down 15 of the first 16 he faced and worked 7.0 innings, allowing five runs on eight hits for his 20th career win, moving him into a tie for sixth all-time at UGA.
"We set a good tempo for the weekend," said head coach David Perno. "The guys are ready to hit. All in all it was a good performance and we were ready to play. We got the long ball going and the power lineup worked tonight. I also thought our infielders did a great job defensively."
Poythress gave Georgia a 2-0 lead with a two-run blast in the first to extend his hitting streak to 13 games. Michael Demperio led off the third with the Bulldogs' first double, then scored on a double to left center by Davidson. Poythress then hit his second home run, and Massanari made it back-to-back with a solo shot to right center giving Georgia a 6-0 lead.
May led off the fourth with Georgia's third double and crossed the plate on a Levi Hyams single. Davidson hit another double with two outs to score Hyams and extend the lead to 8-0.
The Bulldogs added three more runs in the fifth on a home run by Lewis, a double by Lyle Allen and a single by May.
After Tennessee (11-13, 1-6 SEC) scored three runs in the sixth and two in the seventh, Poythress doubled to left field in the eighth and scored for the third time on a single by Massanari. The Vols added another run in the ninth for the final margin.
Nick Hernandez (1-3) allowed eight runs on eight hits in 3.2 innings to take the loss. Georgia will go for its sixth straight league win in game two Saturday at 4 p.m. Junior lefty Alex McRee (2-0, 0.57 ERA) will get the start for the Dogs.