The 73's grabbed a 2-0 series lead with a 6-2 win over the Flyers in Petrolia.
Essex actually trailed 2-1 after the opening period however a natural hat-trick by Luke Gecse helped push them to the win.
Cody Leeming, William Stadder, and Matt Zelko added the other Essex goals.
Curtis Helps and Drew Morgan had the Petrolia goals.
The third game in the series goes tomorrow afternoon at 3pm in Essex.
Also last night, Lakeshore grabbed a 2-0 series lead over the Blades, thanks to a 4-2 win in Blenheim.