Laura Diaz made the most of her first tournament start of 2018 on Friday, carding a five-under-par 66 to grab a share of the lead at the ShopRite LPGA Classic in New Jersey.
Diaz carded a flawless round at the Stockton Hotel and Golf Club at Galloway, posting five birdies and no bogeys.
Diaz -- revelling in having her 12-year-old son Cooper acting as caddie -- had initially planned to only play the pro-am before seeking a place in the draw through qualifying.
The 43-year-old, whose only two victories on the LPGA Tour came way back in 2002, said she had few expectations heading into the 54-hole event.
"Just get it off the first tee, just go and have fun," Diaz said.
Her excitement stemmed from having her son working the bag for the first time.
"It's something I've always dreamed about," Diaz said. "Having him with me was a lot of fun, just so special.
"I've (caddied) for my brother, my father did it for me, my husband's done it for me. I grew up in a family of golfers. It's cool to share the love and passion of a sport.
"So to do it with my own child was awesome."
Diaz finished the day at the top of the leaderboard alongside France's Celine Herbin and Sweden's Anna Nordqvist.
Herbin, the world number 269, produced a dazzling birdie-birdie finish to complete her 66.
The Frenchwoman, who carded six birdies during her round, might have taken sole possession of the lead had it not been for a bogey on her 14th hole of the day.
World number 45 Nordqvist meanwhile relied on a red hot putter to help compile her 66, which like Diaz featured five birdies with no bogeys.
Starting on the 10th, Nordqvist snagged her first birdie on the par-four 12th hole, rolling in a 15ft putt from the apron.
She followed it with a birdie on the par-three 17th after firing her tee shot to six feet.
Three more birdies over the closing nine holes left her at five under.
The leading trio will have little breathing space heading into Saturday's second round.
A low-scoring opening day left a group of eight women just one shot off the lead at four under heading into the weekend.
They include former world number one Lydia Ko, who posted five birdies and one bogey for her 67, and ANA Inspiration winner Pernilla Lindberg.