Larsen beat Ally McDonald with a 14-foot birdie putt on the par-3 18th on the first extra hole at Alaqua Country Club. Both players shot 4-under 67 to finish at 18-under 266, one off the tour record of 19 under set by Jennifer Song in the 2010 Tate & Lyle Players Championship in Decatur, Illinois.
The event was moved from LPGA International in Daytona Beach to Alaqua on Saturday because of Hurricane Matthew. The tour was scheduled to play the IOA Golf Classic last week at Alaqua, but that event was canceled because of the hurricane.
Larsen earned $30,000 to jump from 69th to 20th on the money list with a four-event total of $41,677, enough to get a spot in the final stage of LPGA Tour Q-school. She was the Ladies European Tour's 2015 player of the year and is ranked 87th in the world.
McDonald made $19,234 to finish second on the money list with $110,359. She finished second four times this season and was third twice.
Belgium's Laura Gonzalez Escallon was third at 13 under after a 67. She was fifth on the money list with $77,997.
Sweden's Madelene Sagstrom, the runaway money champion with a tour-record $167,064, had a 64 to finish fourth at 7 under. She led the tour with three victories.
Jackie Stoelting was third on the money list with $97,886, and Wichanee Meechai fourth at $86,217. Sherman Santiwiwatthanaphong was sixth at $77,555, followed by Dana Finkelstein ($76,314), Marissa Steen ($72,496), Nelly Korda ($70,129) and Peiyun Chien ($67,577). Chien edged No. 11 Clariss Guce by $1,104 and No. 12 Erica Popson by $1,191.
Princeton's Emma Talley shot a final round 74 and finished the tournament tied for 29th at 1 under. Talley finished 26th on the Symetra Tour money list with $35,786.
Talley did not earn an LPGA card this season on the Symetra Tour, but she did earn an exemption into the final round of Qualifying School.
