American Lexi Thompson came from behind to earn her fifth career USLPGA Tour win on Sunday, firing a six-under 65 for a one-shot victory in the Meijer Classic.

Thompson, who placed third at the Women’s PGA Championship earlier this year, finished the week at the Blythefield Country Club at 18-under-par 266.

Her score was four shots better than the previous tournament record of 270 set at the inaugural event by South Korean’s Lee Mi-Rim and Park In-Bee in 2014 – when Lee beat Park in a playoff for the title.

American Lizette Salas began the day with a four-shot lead and closed with a one-under 70. She finished tied for second at 17-under 267 with Gerina Piller, who shot a seven-under 64.

Australia’s Sarah Jane Smith was the best placed Australian, finishing 10 strokes behind the winner for a share of 16th spot.

Compatriots Katherine Kirk (one-under), Minjee Lee (two-over) and Sarah Kemp (three-over) all registered disappointing campaigns.

But there was no stopping Thompson.

“Really, the whole day I was just trying to play my own game,” said Thompson, who had eight birdies and two bogeys in a round capped by a two-foot putt for par at the final hole.

“I was just trying to focus on my own game, focus on my pre-shot routine and having fun in between shots and I think that’s what helped me shoot six-under today.”

Thompson got off to a fast start in her bid to make up the deficit on Salas, nabbing four birdies with a bogey in her first seven holes before a birdie at the eighth gave her the lead.

She stretched her advantage to as many as three shots after the 16th, but after she bogeyed 17 – which Salas birdied – both Salas and Piller were within one.

Thompson said her recent work on the mental aspects of her game paid off as she was able to stay calm through the ebbs and flows of the round.

“That has helped me out tremendously just to relax and have fun instead of just grinding 24/7 on the golf course,” she said. “It’s helped me out a lot.”