Choi hit 3-wood to the left side of the fairway and a 52-wedge to a tiny spot on an elevated green she couldn't see.
"Left side of the fairway is a better angle to the second shot," Choi said. "I think the pin was at 79 yards, but I just landed it almost at the pin. I tried to land it almost to the pin. There's not a lot of room."
It checked up and trickled to 3 feet, and she was on her way.
Brittany Lincicome also closed with a 70 at The TwinEagles Club for finish alone in third. Karrie Webb had a 69 to finish another shot behind.
"I'm really happy with how I played this season," Choi said. "I won my first major and even this tournament is very big for me. I think I can have even bigger expectations now and think I deserve it."
She is becoming known as "Big Apple" because of her initials — NYC — and she sure knows how to pick the right tournaments to win. Her wins at the U.S. Women's Open and the Titleholders provided about 55 percent of her season earnings. This win couldn't have come at a better time.
Her mother came over to help her buy a new house in Orlando on Monday.
"I talked to my mom last night and said if I win this week we can buy a bigger house," Choi said.
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