Stacy Prammanasudh is alone in second place after an opening-round, 5-under-par 67. Candy Hannemann, Pat Hurst, Wendy Ward and Mi-Hyun Kim share third place at minus-4.
Overnight rain and a 30-minute delay to start the round made the Ironhorse Course at Vanderbilt Legends Club quite soggy. Players took relief from casual water and some wind made play difficult in the inaugural event.
Scranton parred her first six holes then took advantage of the par-5 seventh. She pitched her third to inches and tapped in for the birdie. Scranton made it back-to-back birdies with a 4-footer at the par-4 eighth.
Scranton played steady early in her back nine with a 3-foot birdie putt at the 10th. She made her move to first with a 10-footer for birdie at the 15th hole.
The 43-year-old hit a sand-wedge to four feet to set up birdie at the 17th and match Prammanasudh in first place. Scranton laid up at the closing par-5 at Vanderbilt Legends Club, then hit another sand-wedge to 4 feet. She holed the birdie putt to polish off her bogey-free round.
'It's nice and was very easy today,' said Scranton, whose last victory on the LPGA Tour came in 2000. 'I've been playing so much better than my scores. I'm getting a little bit better and a lot closer.'
Prammanasudh opened on the back nine Thursday and wasted little time in getting into red figures. She knocked a 9-iron to 6 feet at the par-4 11th to set up her first birdie of the round. She made it two in a row at the par-3 12th when she rolled home a 20-footer.
Prammanasudh, a two-time winner last year on the Futures Tour, hit a poor wedge for her third shot at the par-5 14th but drained the 25-foot birdie putt to reach 3 under for the championship.
The University of Tulsa graduate parred her next nine holes while no player made a move up the leaderboard. Prammanasudh returned to her birdieing ways at the sixth when she sank her second 25-footer of her opening round.
At the par-4 eighth, Prammanasudh's 17th, she hit a spectacular 9-iron to 4 feet. She converted the birdie try to break free of the logjam for sole possession of second place.
'I was just hoping to play well today,' said Prammanasudh. 'I'm hitting the ball a lot better than I have the last few weeks, so I'm just going to try and keep it going.'
Angela Stanford, who lost in a playoff at last year's U.S. Women's Open, shot a 3-under 69 on Thursday and is tied for seventh place with Wendy Doolan, Lorie Kane and Gloria Park.
Karrie Webb opened with an even-par 72.