The runner-up in this year's Australian Amateur Championship and winner of the Lake Macquarie Amateur, Nisbet is playing a series of amateur events in the US, along with other Australians and New Zealanders.
Should Nisbet go on to win the event he is assured of a place in the field at the PGA Tour's RBC Heritage Classic at Hilton Head in 2013.
New Zealander Ben Campbell improved with a round of 69 to be in a share of 5th position at 3 under although six shots behind Nisbet with Tasmanian Ryan McCarthy in a share of 8th position.
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