Seymour's game-winner capped a late 17-point comeback for the Commodores (4-3, 1-3 SEC), who snapped a 10-game home losing streak to Georgia dating back to 1991.
The win was also Vanderbilt's first in 17 games against ranked opponents -- the first such triumph since a 2008 victory against Auburn.
The comeback was enabled by a series of Bulldogs mistakes in the second half.
Georgia (4-3, 3-2), meanwhile, dropped a second straight conference game for the first time since 2010.
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