Lexi Thompson was the best this week and Ariya Jutanugarn was the best all season on the LPGA.
Neither left any doubt about that on Sunday.
Thompson shot a final-round 70 to finish at 18-under 270 and win the season-ending Tour Championship by four strokes from Nelly Korda.
The win makes this the sixth consecutive year that Thompson has won at least once, extending the longest active streak on the LPGA Tour.
"It's very gratifying," Thompson said.
"This is such a special event for me in general, growing up in Florida ... It was just very gratifying."
Jutanugarn took the other two big prizes that were up for grabs this week, clinching the year long Race to the CME Globe prize – and the US$1 million (AU$1.4m) bonus that comes with that – as well as the Vare Trophy for winning the season's scoring title.
The World No.1 Thai had already wrapped up Player of the Year honours, and finished 2018 with a 69.415 scoring average to edge West Australian Minjee Lee (69.747) for the top spot there.
Jutanugarn shot a six-under 66 on Sunday, to finish the week tied for fifth at 12-under 276.
"It felt great today," Jutanugarn said. "I'm very proud of myself."
World No.5 Lee closed with a 70 to be in a share of 37th at one over. Her compatriot Katherine Kirk (72) was the best of the Australians at one under in a tie for 27th.
RIGHT: Jutanugarn poses with the spoils of her 2018 season on the LPGA Tour. PHOTO: Michael Reaves/Getty Images.
Jutanugarn made four birdies in a six-hole stretch midway through her round and the trophy was locked up when she birdied the par-5 14th, before she finished in style with a birdie on the last.
The 13th hole on Sunday provided the shift that Thompson used to hold off Korda. They went to the tee of that par-4 with Thompson up by two; she made birdie, Korda made bogey, and Thompson was suddenly up four with five holes to play.
"It was just very special to win in front of all my family and friends," Thompson said.
It was the 10th career win for Thompson, who grabbed the lead on Friday and kept it the rest of the way.
Brittany Lincicome (67) finish tied for third at 13-under with World No.3 So Yeon Ryu (68).
Former World No.1 Lydia Ko went 68-68 on the weekend to finish 12-under alongside Jutanugarn, Marina Alex (69) and Carlota Ciganda (70).