PHOENIX -- The determined Texan who wore a back brace 18 hours a day for six years as a teen has fought her way to the top of women's golf.
Diagnosed with scoliosis when she was 11, Lewis had to have major back surgery when the brace failed to correct the curvature in her spine.
"I was going into surgery to put a rod and five screws in my back," Lewis said. "That was just 10 years ago. That's not normal, that's not supposed to happen. I mean, I'm not, I'm really not supposed to be here. People with metal in their back, how do you play golf? I don't know. I don't know how. I don't know why I'm here. I know that there's a reason and I know that everything happens for a reason."
Coming off a victory two weeks ago in Singapore, the 28-year-old Lewis won her seventh LPGA Tour title. She won the 2011 Kraft Nabisco and has six victories in her last 23 events.
"I'm having a blast on the golf course, and to be No. 1 in the world, it's what everybody out here on tour is working for and to be that person is, I mean, I really don't even know what to say," said Lewis, the tour player of the year in 2012 after winning four times.
She's the second American to top the rankings, which began in 2006. Cristie Kerr was No. 1 for five weeks over three stints in 2010.
"It's crazy," Lewis said. "That was my goal kind of since the middle of last year and I really didn't think it would be possible this quick. ... I'm going to have fun, I know that. I watched Yani struggle with it for too long and I'm going to go have fun."
Lewis beat Ai Miyazato by three strokes, closing with an 8-under 64 at Desert Ridge to finish with a tournament-record 23-under 265 total on the cactus-lined Wildfire layout. Miyazato, three strokes ahead with six holes to play, finished with a 71.
The tournament turned with a three-stroke swing on the 16th hole, a day after Lewis was penalized two strokes for her caddie's blunder on the short par 4.
On Sunday, Lewis took a two-stroke lead with a birdie after Miyazato made a double-bogey following an errant approach shot that left her with an unplayable lie in a desert bush.
Miyazato took an unexpected four-stroke lead over Lewis and Jee Young Lee into the final round when Lewis was penalized after play Saturday when it was ruled that caddie Travis Wilson tested the sand before Lewis played out of a bunker on No. 16.
"I wasn't even mad at him because he didn't do anything on purpose," Lewis said. "I just felt really bad for him just because all the stories were, 'Stacy Lewis' caddie, Stacy Lewis' caddie.' The spotlight was on him and he never wants that. We were so motivated today."
Miyazato was a stroke ahead on the 16th tee and was seemingly in perfect position after splitting the fairway on the 307-yard hole. But the straight-hitting Japanese star's pitching wedge sailed left, hit on the bank near the edge of the green and rolled into the desert bush.
"My shot was like totally in between clubs," Miyazato said. "I hit the pitching wedge, but my instinct said that it was an easy 9, so it was a little bit indecisive and that's why I pulled my shot."
Instead of playing again from the fairway, she elected to drop in sand in the desert, leaving her with an uphill shot with little green to work with. Her shot from the desert went to the far edge of the green and she two-putted for a double-bogey 6.
"I decided I would take a drop almost like in a bunker position and I thought we had that little backstop behind the pin, so I thought I could make it stop a little bit more," Miyazato said. "It was kind of a little flat when I dropped, so it was hard."
Lewis, a 12-time winner at the University of Arkansas, found the right fairway bunker off the tee, hit to 15 feet and holed the birdie putt.
"I was shocked that she hit the shot she did," Lewis said. "That is not like Ai at all. She's green, green. I mean, it's boring to play with her because she hits so many greens."
Lewis added an 18-footer on the par-3 17th for her third straight birdie.
"I was certainly surprised she finished the way she did, but to make those two putts I did on 16 and 17 was pretty unbelievable," Lewis said. "I'm really speechless. I played great and I was super motivated from all that happened yesterday and just happy for Travis.
"Weird things happen when you play enough golf rounds and I told him that over and over and over again. He would have felt horrible if we lost by two, so that's why I just put the dagger in and made some more putts there coming in."
Miyazato also tied for second last year at Desert Ridge, a stroke behind Tseng. The nine-time tour winner was playing for the first time since suffering a whiplash injury in a five-vehicle crash last month in Bangkok after the LPGA Thailand.
"All in all, I had a good day," Miyazato said. "I have a good feeling and my play was really solid, just the one bad shot on 16. I was a little disappointed."
DIVOTS: Lewis earned $225,000 to push her tour-leading total to $526,364. She donated $50,000 to LPGA-USGA Girls Golf. ... Angela Stanford was third at 17 under after a 68. ... Tseng shot a 70 to tie for 59th at 4 under. ... Lee, the second-round leader after opening 65-64, closed 72-72 to tie for fourth at 16 under.