Adam Ruzicka scored his second goal of the game at 2:57 of overtime and the Sting stopped the Storm 4-3.
Curtis Egert and Jamieson Rees also chipped in for the Sting who improve to 18-4-1
Sarnia, the number one ranked team in the country, sit one point up on second place Sault Ste Marie in the West Division.
Sarnia hosts London Wednesday night. The Knights blanked Windsor 4-0.