Kim Sei-young fired a five-under-par 65 to take a one-shot lead at the halfway stage of the LPGA Tour's Pelican Women's Championship in Florida on Friday.
The 27-year-old world number two from South Korea produced a bogey-free round at the Pelican Golf Club layout, notching five birdies and 13 pars to head into the weekend on eight under for the tournament.
Kim, brimming with confidence after her maiden major triumph at the Women's PGA Championship last month, was in the groove from the first tee, bagging back-to-back birdies on the opening two holes.
Another pair of birdies on the sixth and seventh holes took her to seven under at the turn before her fifth and final birdie of the day on the 14th hole.
Ally McDonald of the United States is one behind Kim in second place after shooting a four-under-par 66.
McDonald, who is chasing her second tour victory after winning the LPGA Drive On Championship in October, teed off on the back nine and reeled off consecutive birdies on her eighth, ninth and 10th holes to move to seven under.
There was a brief stumble with a bogey five on the par-four second, McDonald's 11th hole, but the 28-year-old from Mississippi recovered to pick up her fifth birdie on the par-five seventh.
McDonald said afterwards her breakthrough win at the Drive On had helped settle her nerves.
"I don't feel as stressed about things since I got that win under my belt," McDonald said. "I'm still carrying some positive momentum from that."
First round leader Sophia Popov is one adrift of McDonald in third place alongside Northern Ireland's Stephanie Meadow on six under.
Popov had lit up the course on Thursday with a six-under-par 66 when she pocketed six birdies on the front nine alone.
But the British Open champion found the going tougher on Friday after teeing off on the 10th. Two early birdies took her to eight under before she dropped a shot with a bogey on the 16th.
She recovered with a birdie just after the turn to back to eight under, but then stuttered with a double-bogey six on the par-four second hole.
Popov was kept in contention with some solid putting including a trio of puts from between 10-15 feet which helped her make a level-par 70.
"I grinded it out and I made a lot of par putts coming in, so I'm pretty happy with my score," the German said.
Meadow, meanwhile, charged up the leaderboard with a barnstorming finish en route to a five-under-par 65.
Meadow, who began the round on one under, dropped down the leaderboard with a bogey on her opening hole after teeing off on the 10th.
But birdies on the 12th and 14th holes left her two under. After a run of eight consecutive pars, Meadow then erupted down the stretch with four birdies in her final five holes to move to six under.