The Australians and Brits have blitzed the field and share five race wins between them as well as several top five results.
"It's a change of scene and change of course tomorrow," said Belcher. "We'll come out fighting. We're confident - it's close."
Two fleet races remain ahead of the Medal Race on 9 August and the Australians and Brits will want to put some daylight inbetween each other at the top of the tree.
1. Mathew Belcher and Malcolm Page (AUS) - 16pts
2. Luke Patience and Stuart Bithell (GBR) - 17pts
3. Gabrio Zandona and Pietro Zucchetti (ITA) - 46pts
4. Lucas Calabrese and Juan de la Fuente (ARG) - 46pts
5. Paul Snow-Hansen and Jason Saunders (NZL) - 47pts
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