Graham Knott scored his second goal of the game in overtime to lift the Windsor Spitfires over the London Knights 3-2.
The win gives the Spits a 3-1 lead in their OHL Western Conference quarterfinal.
Gabe Vilardi scored Windsor's other goal, and Jeremy Bracco had two assists.
Michael DiPietro made 31 saves for the Spitfires.
Game 5 in the series goes Friday in London.
AM800's coverage begins with the pre-game show at 7:05pm.