With her lead cut from four strokes to one, Ji aced the 142-metre 14th with a seven-iron, the ball bouncing and rolling into the hole, to push her advantage back out to three shots.

Ji finished with a five-under 67 at Aviara for a two-stroke victory over Kerr and Lizette Salas in the final event before the ANA Inspiration next week at Mission Hills.

Ji finished at 16-under 272. The 31-year-old South Korean earned $270,000 and two Kia cars; a Sorento for the hole-in-one and a Stinger for the victory.

She now has four LPGA Tour victories, including the 2009 US Women's Open.

The 40-year-old Kerr closed with a 68, while Salas finished with a 69.

Minjee Lee and Sarah Jane Smith were the best of the Australians, both finishing nine shots behind the winner for a tie of 26th.