Law shot a closing three-under 67 to win by two shots and claim her first LPGA Tour title in her 56th start.

A 15-foot birdie putt on the 16th hole finally brought success.

"It was definitely a relief," Law said. "I'd hit a really good putt on the previous hole before and it kind of hit a spike mark," after making her sixth consecutive par. "I thought it was middle centre and didn't make that one.

"It was a grind."

The 24-year-old held a share of the lead after the first three rounds and finished with a 17-under 267 total on the River Course at the Kingsmill Resort.

Madelene Sagstrom, Brooke Henderson and third-round co-leader Nasa Hataoka tied for second. Sagstrom shot 66, Henderson 68 and Hataoka 69.

West Australian World No.2 Minjee Lee shot back-to-back 67s over the weekend to rally from a second-round 73 and finish tied 13th at nine under.

Law had come from 10 shots back on the last day to get into a playoff in the LPGA Mediheal Championship three weeks ago in Daly City, California.