Lexi Thompson denied former teen phenomenon Michelle Wie as she became the second youngest winner of a women's golf major in LPGA Tour history.
The 19-year-old fired a closing four-under-par 68 to win the Kraft Nabisco Championship by three shots from fellow American Wie (71), who shot a 71 as she attempted to break a winless streak of almost four years.
"It's just a dream come true," said Thompson after making the traditional victory leap into Poppies Pond next to the 18th green at the Missions Hills course.
Thompson birdied four of the first nine holes to open a five-stroke lead and parred the final nine in a rock solid performance to win the year's first major at 14-under 274.
At 19 years, one month, 27 days she is second youngest major winner to countrywoman Morgan Pressel who set the record in her 2007 victory at Mission Hills at 18 years, 10 months, nine days.
"This was one of my goals coming into the year, to win a major," she said.
"I've always seen myself winning a Kraft Nabisco.
It's such a huge honour with all the history behind the tournament."
The 24-year-old Wie had to settle for second, though she was four shots clear of third-placed Stacey Lewis (69).
Karrie Webb's long search for an eight major title goes on after the Australian great shot a 73 to tie for 11th, 12 shots behind Thompson.
Minjee Lee, the 17-year-old Australian who tops the amateur rankings and is 110th overall, was the low amateur, closing with a 72 to tie to be 24th at even par.
Thompson had only one bogey - missing a 3-footer for par on the 18th Saturday - in her last 55 holes.
Wie, who had three bogeys in her closing round, used her driver only four times, choosing to hit fairway-metal stingers on the other 10 driving holes - leaving her as much as 60 yards behind Thompson.
"I stuck with my game plan and I think it was the right play," Wie said.
"Who knows? In hindsight you would do something here or do something there, make a putt there. That's the way golf is. I just couldn't get anything going today."
Thompson won the 2011 Navistar LPGA in Alabama at 16 to become the youngest winner in tour history, a mark broken by New Zealander Lydia Ko in the 2012 Canadian Women's Open.
Last year, Thompson won the LPGA Malaysia and Lorena Ochoa Invitational titles.
Wie made her 12th start in the event. She was ninth in 2003 at age 13, fourth the following year and tied for third at 16 in 2006. She also was sixth in 2011.
For all her youthful promise she has just two tour victories, winning the 2009 Lorena Ochoa Invitational and 2010 Canadian Women's Open.
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