Stephanie Meadow's bid to win the CME Group Tour Championship took a significant blow after she struggled in round two in Naples, Florida.
After a strong start with a two-under-par 70 in her first round at Tiburón Golf Club, the Jordanstown woman couldn't back it up and carded a four-over-par 76 yesterday to fall 11 shots behind leader Jin Young Ko.
Cavan's Leona Maguire, the only other Irish player in the field, had a better day, recording a level-par 72 to stay at one-over, 10 back of Ko.
Meadow had set herself up nicely going into day two, but an early double-bogey on the second set the tone for the day.
The Galgorm Castle touring professional didn't pick up a birdie in her round, adding bogeys at the 11th and 17th to fall down the leaderboard and into a tie for 47th heading into the weekend.
Meanwhile, Maguire fared slightly better, picking up two birdies to go with two bogeys to finish the day where she started.
The 26-year-old Slieve Russell ace had started her round at the 10th and rattled off eight straight pars before picking up her first shot of the day at the 18th.
Things didn't go so well after the turn, with back-to-back bogeys coming at the third and fourth, but she finished strongly, birdieing her final hole to get into a tie for 42nd.
At the top of the leaderboard, things could not be tighter, with nine players within three shots of the lead heading into the final two rounds, which throw up some great drama.
World No.1 Ko was on song on day two, signing for a bogey-free five-under 67 to take herself clear of the chasing pack at nine-under-par for the week.
The Korean's advantage is just one over defending champion Sei Young Kim, who fired a three-under 69 on Friday, and overnight leader Lexi Thompson, who could manage only a 71 in her second round.
Australia's Hannah Green holds solo fourth at seven-under, while England's Georgia Hall and Germany's Caroline Masson are the best of the European contingent just three back at six-under.
The winner will be not only crowned the Tour Championship champion, but will also finish top of the LPGA Tour's order of merit, the Race to the CME Globe, and will receive a whopping $1.1m (£815k).
Meanwhile, Mount Juliet has been confirmed as the host venue of the 2021 Irish Open, which will be held from July 1-4.