SAN MARTIN, Calif. – How can someone 19 years old be a grizzled veteran? Ask Lydia Ko. The best player in women’s golf is at it once again, lurking on the leader board at a major going into Sunday’s final round of the U.S. Women’s Open.

An efficient 70 in Saturday’s third round at CordeValle capped by a birdie on the final hole put Ko alone atop the leader board at seven-under par, one stroke ahead of 2009 U.S. Women’s Open winner Eun Hee Ji and Sung Hyun Park, with Brittany Lang and Amy Yang two back.

Of those within two of the lead, Ko by far has the most experience getting the job done on Sunday. Park, Yang, Lang and Ji have a combined five LPGA wins while Ko has 13 alone.

“You just never know what's going to happen,” she said about what her mindset will be on Sunday. “All I can do is focus on the shot I have in front of me, try my best at what I'm going to do. What somebody else does is definitely out of my hands. It's hard enough trying to control where my ball ends up. I'm just going to enjoy it.”

This is getting to be old hat for Ko. In her last 13 majors, she has six top-3s, including victories in the 2015 Evian Championship and the ANA Inspiration this year. Three weeks ago, she was second in the KPMG Women’s PGA Championship in a playoff with Brooke Henderson.

Pretty much every record in the women’s game that begins with the word “youngest” ends with the name “Ko.” That includes youngest to win a major and youngest to reach No. 1 in the Rolex Rankings. And when she captured the ANA, she became the youngest with multiple majors since Young Tom Morris – in 1869.

That’s just ridiculous when you have to reach back to when Ulysses S. Grant was president of the United States and William Gladstone prime minister of the United Kingdom to find a comparison for Ko. If she wins on Sunday she’ll be the youngest three-time major winner -- ever.

Right now, she has no comparison in the women’s game. Three of her 13 wins have come this year and she has nearly twice as many Rolex Rankings points as No. 2 Henderson.

Ko’s third round was nothing flashy, but the only thing Ko does flashy is get the ball in the hole in fewer strokes than anyone else. Once again showing uncanny maturity for someone so young, she reverted to the kind of conservative play mode that works well on the weekend at a USGA event when par is your friend.

“No matter what position I'm in, always to finish with a birdie on the last hole is a lot of good memories,” Ko said. “I think I tried to stay patient and calm out there today. The key around major championships is that sometimes a par is a good score and you have to walk off and forget about the bads and focus about the shot you have in front of you.”

On paper, Ko has by far the best resume of those at the top of the leader board. And while it’s true the game is not played on paper, she’s also pretty good on grass. You've got to like her chances.