Shelby Burchell sent a pitch over the center field wall in the bottom of the eighth inning to end the game.
Tournament MVP Ellen Renfroe picked up the win in relief of her sister Ivy Renfroe.
Three other Lady Vols received All-Tournament honors in Spigner, Burchell and Raven Chavanne.
No. 7 Tennessee (47-10) utilized three home runs, including the walk-off solo shot by Burchell, and stellar relief pitching to post the thrilling the comeback win over No. 8 Georgia (47-12) and secure the program's second SEC Tournament crown and first since 2006.
Junior designated player Jessica Spigner registered the third two-HR game of her career, blasting a pair of vital two-run shots as part of her 2-for-3, four-RBI effort against the Bulldogs.
Burchell was 2-for-4, with a pair of runs scored and her walk-off homer on a 0-1 pitch from Georgia's Alison Owen to lead off the bottom of the eighth.
Sophomore third baseman Raven Chavanne was 1-for-4 and scored a crucial tally on a passed ball during the fifth as Tennessee clawed within a single run at 4-3.
In a relief role in the circle, freshman pitcher Ellen Renfroe permitted just a single run on five hits with a walk and five strikeouts over 7.1 innings of work to get the victory and improve to 26-5 overall.
"First of all I would like to say that is a very good Georgia team," Lady Vol Co-Head Coach Ralph Weekly said. "They have six or seven seniors, so hopefully we won't have to see them again unless we are both lucky enough to meet in the Women's College World Series.
"Second of all, everything goes to these guys (speaking about UT players Burchell, Spigner and Ellen Renfroe beside him on the dais). Our team did not quit, we fell down 4-0.
"Most teams would have crumbled but not Tennessee. These guys fought the whole time, they never said die, they kept talking about winning all the way through. It is all about the players tonight."
Tennessee now awaits its path in this year's 2011 NCAA Tournament as the NCAA Selection Show will be broadcast live at 10 p.m. ET on Sunday night (May 15) via ESPNU.
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