(CNN) -- Yani Tseng's two-year reign at the top of women's golf is over.
Five-time major winner Tseng has been at the top of the Rolex World Rankings since February 2011, but the Taiwanese star has finally been usurped by American Stacy Lewis.
Lewis produced an eight-under-par final round of 64 to clinch the Founders Cup in Phoenix Arizona, just two weeks after winning the HSBC Women's Champions event in Singapore.
The Ohio native is only the second U.S. player to occupy the coveted berth after Cristie Kerr also reached the top in June 2010.
Lewis clawed back a three-stroke deficit to Japan's Ai Miyazato to eventually finish three shots ahead of the former world No. 1.
The final round's 16th hole proved decisive, with Miyazato slipping and allowing Lewis to take control.
"It's awesome," Lewis told the LPGA Tour's official website when asked about the win.
"I played great today. Myself and Ai we just went back and forth all day; she was making putts, I was making putts.
"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 and I'm just really speechless."
If Lewis' fightback at the Wildfire Golf Club journey was stirring, it is nothing compared to the story of her rise to the top.
A decade ago the 2011 Kraft Nabisco Championship winner underwent surgery for scoliosis, following a childhood plagued by back problems.
"Yeah, it's almost 10 years ago I was having surgery, I was going into surgery to put a rod and five screws in my back," added Lewis.
"That's not normal, that's not supposed to happen. I mean, I'm not really supposed to be here.
"I know that there's a reason and I know that everything happens for a reason. Every setback you have along the way, everything good that happens, it all happens for a reason.
"I couldn't have dreamed the kid growing up wearing a back brace 18 hours a day that is the No. 1 player in the world. I don't know, I don't know what to say."
Lewis is the seventh player to top the rankings. Tseng, Kerr, Miyazato, Mexico's Lorena Ochoa, Sweden's Annika Sorenstam and Jiyay Shin of South Korea are the only other golfers to have held the distinction.