Jordan Sherratt, overnight leader with Han, fired a third round 2-over-par, 74, to be just three-strokes behind Han at 7-under-par.
Sherratt, winner of the Barrett Amateur in Canada in June and the Riversdale Cup this year, fired earlier rounds of 68-67 and was set to have his third round going well after opening with a birdie on the first.
With bogeys on the 5th and 7th, Sherratt made the turn at 1-over-par. The back nine for the South Australian again produced bogeys on the 13th and 17th but a birdie on the 16 resulted in two nines of 37 to finish with a 2-over-par, 74.
New Zealand's Peter Spearman-Burn is in fourth place and one stroke behind Sherratt at 6-under-par, after rounds of 69-68-73. Matthew Giles is the next placed Australian behind Sherratt in a tie for 18th following rounds of 71-71-73 at 1-under. Daniel Nisbet is at 1-over with rounds of 72-72-73, in a tie for 22nd. Brendan Smith is at 3-over-par for the tournament, whilst Matt Jager finds himself in a tie for 30th position with Smith, following rounds of 72-73-74.
Han, the 21-year-old winner of the individual title at last month's Nomura Cup (Asia Pacific Teams Championship), finds himself one round away from playing at 2010 Masters and securing a spot in the International Final Qualifying for The Open Championship next year at St Andrews.
The South Korean, 191st in the world amateur ranking, has predominantly played junior golf for the last two years, finishing runner-up at the 2009 Callaway Junior World Championship.
Han will have to watch the fast moving Eric Chun who's third round 66 was the day's low round, moving him eight positions after starting the round in a tie for 10th position.
Chun is well known in Australian golfing circles having played his junior golf in Sydney before moving into the US collegiate system in 2008.
The South Korean native has won numerous junior titles in Australia, including the 2005 New South Wales Junior Championship and in 2004 finished second at the Mastercard Junior Masters behind Ben Pisani. Ã‚Â In 2009 he qualified to be an alternate for the 2009 US Open after making it to the final round of qualifying before falling in a three-way playoff.
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