Mulroy's birdie binge gave him an 8-under-par 64 for the third round and put him at 15-under 201 after 54 holes going into Sunday's final round.
Felipe Aguilar, who had a second-round 64, shot 4-under 68 Saturday and is alone in second at 13-under. Jbe Kruger, the second-round leader, slipped to a 1-over 73 Saturday and is tied with George Murray (69), Hennie Otto (67) and Peter Whiteford, who had a bogey-free 64 Saturday, for third at 12-under.
Mulroy opened Saturday's play with back-to-back birdies and, after a birdie at the sixth hole, was 3-under after 12 holes. He then ran off five consecutive birdies and jumped into the lead.
Aguilar also closed fast, posting birdies on five of his last six holes.