Reigning WAFL premiership coach John Dimmer has been appointed State coach for 2010 but will face the tough task of avenging WA's embarrassing hiding against Victoria in their previous meeting.

The Black Swans suffered one of their worst-ever losses in 2007, travelling to Port Melbourne where a side captained by Brownlow medallist Shane Woewodin was thumped by 119 points.

Dimmer, 55, admitted the thrashing would act as motivation for this year's clash at Medibank Stadium on May 22.

He said WA would look to build on the thrilling one-point victory over South Australia last year as they attempted to defeat the Vics for the first time since 1991.

"The only team that we haven't beaten in the last few goes is the VFL, so there's a fair bit resting on it," Dimmer said.

"I'm not saying we're going to have bragging rights or we're the best State because you have to beat South Australia and the VFL on a consistent basis before you can claim that, but I think we are progressing up the inter-State ladder."

Dimmer was offered the prestigious job after leading South Fremantle to the club's 13th flag last year and will coach WA for just the second time.