Shawnee Heights pitcher Austin Higgins held St. Thomas Aquinas in check for six innings while his team built up a 2-0 lead.
But it all unraveled in the seventh inning as the Saints made their comeback and finished the game in walk-off fashion with a two-run double from Tyler Watson.
The Saints scored their first run on a throwing error that chased Higgins from the game and brought on Zach Holmes for the Thunderbirds.
The T-Birds finished the game with three hits and scored both of their runs in the fourth inning.
Higgins took the loss for the T-Birds, while Watson was the winning pitcher for the Saints.