The long-bomber shot a final-round 70 Sunday to get into a playoff with Jin Young Pak at the Alliance Bank Golf Classic, and then clipped Pak on the fourth hole of the sudden-death playoff at The Links at Erie Village.
Welch, 25, overcame Pak and several weather delays to shoot 9-under-par 204 and collect the $12,600 first-place prize.
After Welch and Pak traded par putts through the first three holes of extra play, it came down to who could have the closer approach shot. Welch stuck a gap wedge from 107 yards out to about 6 feet from the pin and two-putted for par. Pak lipped out her par attempt, handing Welch the victory.
Im so excited and really proud of myself, Welch said. Ive known all year that I could do it and now that the season is coming down to the end, I knew I had to get a win to try and get into the top-5.
It was Welchs second playoff of the year, as she came up short against Sunny Oh at the season-opening Bright House Networks Open in Lakeland, Fla.
Welch took advantage of the rain delays by making birdies on both occasions after play resumed. Prior to the second weather delay, Welch ripped her tee shot off the 16th hole and converted a 3-foot birdie putt.
It was a day to stay patient as two weather delays spanned nearly five and a half hours. Play was first suspended at 11:19 a.m. due to lightning. Nearly two hours later, play resumed under a muggy heat wave, but play was stopped again because of a severe thunderstorm at 3:09. Play resumed for the final time almost three hours later.
Shortly thereafter, Welch won, recording her second big victory in consecutive weeks.