Barnes at 10 under won the event by two over Porter, with Senior three further back but alone in 3rd position and two ahead of Aaron Townsend and Steve Jones.
Barnes second round of 64 blew the field apart after Porter had led with an opening round of 4 under 68.
For Porter it is the third time he has managed to snare one of the Open qualifying spots via IFQ in the last four years having previously earned starts in 2007 and 2008 when the event was held at the Lakes Golf Club in Sydney.
50 year old Senior continues a dream run of late having earned his Champions Tour card six weeks ago and finished 4th at last week's Victorian Open. Senior will have the thrill of being able to play the Open Championship in July a week before the Senior British Open at Carnoustie.
Barnes too is in a very good place in his life having earned his Japan Tour playing privileges last month after finishing on top of the Qualifying School there.
All three will be playing at the opening event of the Nationwide Tour season, the New Zealand Open although Senior heads to the US a week after the tournament in Queenstown to make his debut on the Champions Tour at the Ace group event in Naples, Florida.
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