Lexi Thompson has already made LPGA history, becoming the youngest winner of a tour event at age 16, but she is going to have to wait even longer before becoming a member of the tour. The home-taught US high school senior won the LPGA Navistar Classic on Sunday, taking a $195,000 top prize and shattering the youngest win mark of 18 years and two weeks set by Marlene Hagge at the 18-hole Sarasota Open in 1952. That would normally be good enough to claim a place in the LPGA, but Thompson does not meet the minimum age requirement of 18 years old. "I don't really know right now," Thompson said about her LPGA plans. "This is a really big thing going on right now. I will think about it in the next few days." Thompson had to petition the LPGA for an exemption to compete in the qualifying event for the 2012 LPGA season. She won the first of three stages in the "qualifying school" by 10 strokes in July. Despite being one of the top American personalities on a tour struggling to rebuild after losing several US events in recent years, Thompson must play her way through qualifying to earn LPGA membership in 2012. "Should Lexi qualify for LPGA membership via her Q-School performance, she will be an LPGA member for the 2012 season," LPGA commissioner Mike Whan said. US veteran Juli Inkster said any delay in having Thompson take her place among the sport's elite was ridiculous in light of her performance last week. "It's kind of silly," Inkster said. "I think it makes us, the LPGA, look bad too. She has proved she can play out here. Now you have to go to qualifying school? To me that's silly." Scott Thompson, Lexi's caddie and father, said a decision on whether or not she will try for full 2012 LPGA membership has not yet been made. "We haven't even really talked about that yet," he said. "We'll worry about that as it comes. We'll see." Thompson, the sister of US PGA player Nicholas Thompson, shared the 36-hole lead at the same event two years ago but faded. Last May, she shared the lead after 54 holes in Mobile, Alabama, but finished with a 78 and shared 19th.