A third round 3-under-par, 69, allowed McGraw to take a commanding six shot lead heading into the final 18-holes where he battled horrendous conditions in the afternoon for a four-over-par 76 to secure his first main amateur title finishing at 2-over-par for the championship.
Second round leader, Dimitrios Papadatos, found it tough in the morning round where he recorded 4-over-par, 76, and closed with a 1-over-par, 73, to finish outright second at 5-over-par for the tournament.
Australian Amateur Stroke Play and Australian Boy's champion, Cameron Smith, made his charge early on the final day with rounds of 1-under-par, 71, and a final round of 76 to finish outright third at plus-9.
The top-16 qualify for the Queensland Men's Amateur Championship to be played at Arundel Hills Golf Club from the 3rd May, with the 36-hole final scheduled for Friday week.
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