Thompson, who does not meet the 18-year age limit to be an LPGA member and still won't be granted membership despite her victory, overpowered the field with 280-yard tee shots and finished 17-under-par 271, five strokes clear of Tiffany Joh, despite lugging the excess baggage of history around RTJ Golf Trail. Wie, meanwhile, a two-time winner on the LPGA, finished 24 strokes behind Thompson.
"Coming up the 18th, all the pressure was let off," Thompson said after being doused with water rather than champagne following her win. "I knew I could have the record, but I just focused on playing the golf course. I was a little nervous, but if you are not nervous you don't care."
Earlier this year, Thompson petitioned the LPGA to attend Qualifying School despite her age. Commissioner Mike Whan granted the request and said she will be given an exception to the age rule if she advances through Q-school. Thompson, who turns 17 in February, dominated at Stage I Q School and plays Stage II the week of Sept. 26 in Venice, Fla. The final stage begins Nov. 30 in Daytona Beach, Fla.
Related: Alexis Thompsons swing sequence
With the victory at Navistar, Lexi "will qualify for our CME Group Titleholders season-ending event," Whan told GolfDigest.com. "Her win does not qualify her for anything else." He added: "Should Lexi qualify for LPGA membership via her Q School performance, she will be an LPGA member for the 2012 season. Should she qualify, via Q School, no other Petition is required," meaning she would not have to ask for a further exception to the age rule.
A victory in an LPGA event usually comes with automatic tour membership, but Thompson is being denied that benefit because of her age. There is a chance the Thompson family could still petition Whan for an exception to the age rule -- a request he would be hard-pressed to deny. In the past, Whan has said he didn't want to take any action that could be perceived as encouraging kids to quit school to play golf.
Thompson displayed a sharp learning curve on Sunday in Alabama. At the Avnet LPGA Classic this year, Lexi went into the final round tied for the lead with Song-Hee Kim but collapsed to a 78 to finish T-19. She did not let that happen at the Navistar, despite a back-nine charge by Joh, who made four consecutive birdies and cut what was once at seven-stroke margin to three. But birdies on Nos. 16 and 17 by Thompson ended the suspense.
The emergence of Thompson as a star would be a big boost for the LPGA, which has expanded greatly in Asia as players from Korea, Japan and now Rolex Rankings No. 1 Yani Tseng from Taiwan, have dominated. But it has lost events in long-time American markets like Corning, N.Y. Lexi, who is nearly six feet tall and bangs the ball a long way, could be a crowd favorite. The last American to be LPGA Player of the Year was Beth Daniel in 1994.
Thompson will not only be forced to watch the Solheim Cup on TV this week, she then has to go to the second stage of Q school the following week despite being a tournament winner. But watching her Sunday, you get the feeling that not only won't slow her down, it will likely get her engine running faster. It may be early to make this call, but let's say it: Lexi Thompson is the real deal.
-- Ron Sirak
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