World number 304 Sophia Popov won the Women's Open by two shots at Troon, Scotland.
The 27-year-old German, who had not won on the LPGA or Ladies European Tour before, shot a three-under 68 in the final round.
Thailand's Jasmine Suwannapura finished second, two ahead of Minjee Lee.
Seven-time major winner Inbee Park was the only other player to finish under par, after a 66 saw her end one under.
Popov is the lowest-ranked player to ever win a women's major.