McGrory leads by a stroke over Adam Mollis, after Mollis carded even-par round to be in outright 2nd position with Sam Daley at 1-over-par and in 3rd position.
Cameron Smith, considered by most to be the tournament favourite, opened with a 2-over-par,74, to be three strokes behind McGrory in share 4th position with Daniel McGraw and Tim Hyland.
Tim Hart, runner-up last year in the Queensland Amateur to Brett Drewitt, is in 7th position after a 3-over-par, 75, with Kevin Marques, Nicholas Smits and Maverick Antcliff.
The top-16 following Friday's 36 hole final round will 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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