Cliff Floyd singled with one out in the ninth against Bobby Jenks and was replaced by pinch-runner Angel Pagan. Daryle Ward singled Pagan to third and then Theriot squeezed him home.
Alfonso Soriano led off the game with a homer for the second straight day and the White Sox pulled even on a Jim Thome groundout in the bottom of the first.
Michael Wuertz got one out for the victory, while the loss went to Jenks. Bobby Howry pitched the ninth for his first save.
The White Sox have lost 21 of their last 26 games.