Mitchell Stephens goal midway through the second period was the game-winner as London beat Windsor 2-1 to remain alive in the OHL playoffs.
Jeremy Bracco scored the Spitfires' lone goal, and Michael DiPietro made 24 saves.
Tyler Parsons was sold in the Knights' goal stopping 28 shots.
Windsor leads the best-of-7 Western Conference quarterfinal series 3-2.
Game 6 will be at the WFCU Centre Sunday afternoon.
AM800's coverage begins with the pre-game show at 1:30pm