Gemma Dryburgh claimed back-to-back wins in the Rose Ladies Series in windy conditions at Royal St George's.
The 27-year-old Scot's one-under 69 was enough to see off England's Charley Hull and Georgia Hall, who finished with level-par rounds of 70.
It was the first professional female tournament to be hosted at the Kent course, which is set to hold the rescheduled Open Championship in 2021.
World 221 Dryburgh now tops the series standings with Hull dropping to second.
Dryburgh recovered from a bogey at the first to post birdies at the seventh, 10th and 13th holes before dropping a shot at 15.
And in almost a repeat of the circumstances of her success at The Buckinghamshire, she was able to capitalise when playing partner Hull, the world number 25, bogeyed her final two holes.
The Rose Ladies Series, sponsored by former world number one Justin Rose and his wife Kate, has been set up to fill the gap in the elite women's golf calendar.
The Ladies European Tour will not resume until August after being suspended because of the coronavirus pandemic.
Rose Ladies Series Brokenhurst Manor Winner: Charley Hull Moor Park Winner: Meghan MacLaren The Buckinghamshire Winner: Gemma Dryburgh Royal St George's Winner: Gemma Dryburgh JCB Country Club 16 July Bearwood Lakes 23 July The Shire 30 July North Hants (Grand Final day one) 5 August The Berkshire (Grand Final day two) 6 August Wentworth (Grand Final day three) 7 August The series, which continues at JCB Country Club next week, concludes with a Grand Final that begins on 5 August.
However, Dryburgh is set to miss out on the finale as she heads to the United States to quarantine in preparation for the resumption of the LPGA tour on 31 July.
Rose Ladies Series standings 1.
Gemma Dryburgh 297.
5 points 2.
Charley Hull 281.
Elizabeth Young 195.
Annabel Dimmock 166.
Georgia Hall 160.