MINJEE DISQUALIFIED FOR FAILING TO SIGN CARD

Photo above -- Minjee Lee blasts from a trap during her final round at Kingsmill. Picture: GETTY IMAGES

There are tiny errors – and then are costly, larger ones.

Sadly for Minjee Lee today, she's suffered through one of the more painful variety when she was disqualified from the LPGA Tour's Kingsmill Championship for failing to sign her scorecard.

Lee had been sitting prominently in the top three for much of the final round, but a couple of late errors were exacerbated by a closing double-bogey as she fell to tied 10^th at seven under, 13 shots adrift of runaway winner Lexi Thompson.

But worse was to come for the West Australian who left the official scoring area without having signed her card – a mistake that cost her in the vicinity of $US24,000 – and the Race to the CME Globe points she'd have accumulated.

It was a tough pill to swallow for Lee, who had her LPGA Tour breakthrough win at the same venue in 2015, as Thompson careered away to a record-breaking go-to-whoa win, her first since the drama that dogged her at the ANA Inspiration in April when she was controversially penalised four shots while holding a commanding lead.

Her four-round 20-under-par 268 total, including just two bogeys all week, broke the mark previous tournament record of Annika Sorenstam.

"I was so determined just to keep on working on my game (after the ANA) because I knew that was the best golf I have played," Thompson said.

"I just couldn't let it get to me. I had to continue to practise and work hard. To have the support from my family and friends and all the fans, I mean, it was amazing. Without them, I wouldn't be here.

"I'm so over (the ruling). It's in the past. It's unfortunate what happened, but it's time to move on. This puts a lid on it."

Su Oh was the best "official" Aussie at T36 and one under after a flat closing 76, while Karrie Webb was T55 at two over and Sarah Jane Smith T60 at four over, while Sarah Kemp and Katherine Kirk missed the cut.