Adam Cianciarulo led the way at the start of the 450cc main event, but he was chased down and passed by defending champion Cooper Webb, who went on to take the win.
Blake Baggett scored third on the night to complete the podium, but eyes were mostly focussed on the battle further back between series frontrunners Roczen and Tomac, the two men battling in about seventh position.
Tomac eventually battled through to finish fourth, while Roczen struggled to pass Justin Barcia and finished sixth, the points difference between fourth and sixth allowing Tomac to shave a vital two points off Roczen’s championship lead.
In the 250 West main event, it was Frenchman Dylan Ferrandis who opened up his championship points lead with a calculated race win ahead of Austin Forkner.
Australian riders Luke Clout, Jay Wilson and Aaron Tanti finished sixth, 11th and 14th respectively in the 250cc final.
Photo courtesy Simon Cudby
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