Ogilvy, despite three bogeys, shot an 8-under-par 63 in the third round and is at 13-under 200 going into Sunday's final round. Second-round leader Ian Poulter also had three bogeys and ended up with a 3-under 68, leaving him two strokes back of Ogilvy.
Nathan Green (67 Saturday) and Ashley Hall (68) are tied for third at 9-under with five other players in fifth at 7-under.
Poulter and world No. 1 Luke Donald, both from England, are the only non-Australians in the top 43 after three rounds. Donald is at 2-under 208 and tied for 13th.
Ogilvy opened Saturday's play with an eagle at the first hole and birdies at 2 and 3. His first bogey came at the fifth hole but he had birdies in five of the next seven to get to 8-under through 12 holes.
He countered bogeys at 13 and 16 with birdies at 15 and 18 in taking the lead.
Poulter had a two-stroke lead after Friday and had birdies at the first two holes. He slipped back to even with bogeys at 4 and 8. A birdie-bogey pair at 12 at 13 kept him level but he kept within reach of Ogilvy with birdies at 15 and 18.
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