Hyo Joo Kim captured her third LPGA Tour title when she won the Pure Silk Bahamas LPGA Classic by two strokes on Sunday.
Kim, who finished on 18-under, carded a seven-under-par 66 to begin her 2016 LPGA Tour campaign on a high.
Stacy Lewis, Anna Nordqvist and defending champion Sei Young Kim were in a tie for second on 16-under, while Pornanong Phatlum, who matched the tournament record with an eight-under-par 65, Paula Cremer and Ilhee Lee finished three strokes adrift of Kim in a tie for fifth on 15-under.
Kim started the final round one shot behind Nordqvist and Charley Hull, but took the lead when she made four birdies on the front nine, including three in a row from the fourth to the sixth.
Kim maintained her lead with a hat-trick of birdies from the 12th to the 14th before her lead was cut down to just one when she bogeyed the 16th. However, she restored her two-stroke lead with a birdie at the next hole.
Lewis, who fired a five-under-par 68, was in contention throughout the day, but had to make an eagle on the final hole to force a playoff. That was not to be the case as Lewis could only make par on the 18th and had to settle for second place for the 22nd time in her career.
Meanwhile, Kim, the defending champion, hit a final-round 68, but ruined her chances of victory with a bogey and double bogey at the second and ninth respectively. Despite making four birdies on the back nine, it was too little too late for the 23-year-old.
Nordqvist, who registered a final-round 69, was unable maintain her position atop the leaderboard despite making five birdies and a bogey, while Hull finished in a tie for eighth after recording a 71, which consisted of four birdies and two bogeys.
Rahm replaced Rory McIlroy at the top of the rankings following his victory in the Memorial Tournament.
Seven years of hard work paid off in spectacular fashion for Michael Thompson at the 3M Open on Sunday.
Thompson carded birdies at the 16th and the last to secure his second PGA Tour win of his career.
Tom Lewis, the only Briton to make the cut, will start the final round eight shots off the lead.
The 23-year-old won a second European Tour title.
It was a second European Tour title for the 23-year-old.
The 29-year-old chose to miss the first six events of the PGA Tour to stay with his family in England.
The Italian could become the first player to win a European Tour event without dropping a shot since 1995.
The US PGA Championship takes place at Harding Park from August 6-9.