The win puts Nicholls in contention for selection in the Australian squad to compete at the 2013 World Cup, scheduled for late August in Duisberg, Germany.
After finishing her heat in second place behind Bernadette Wallace, Nicholls was again second in her semi-final behind Naomi Flood.
But Nicholls would not be denied in the final, winning in 2:00.36, less than a second ahead of Flood, who claimed second place.
PerthNow Digital Edition.
Your local paper, whenever you want it.Get in front of tomorrow's news for FREE
Journalism for the curious Australian across politics, business, culture and opinion.
READ NOWUnfortunately for Nicholls the roles were reversed in the K1 200m final, with Flood claiming the victory.
Bayswater’s Jesse Phillips is also eligible for World Cup selection as he teamed with Canning River’s Steve Bird to take out the K2 200m final.