Just like Kaymer, she opened Thursday without a bogey on her card, a 3-under 67 for a one-shot lead over Michelle Wie.
"It was cool to see the plan I had laid out in my head. He was kind of doing the same thing," Lewis said. "So it was nice coming into the week knowing that my plan was going to work on this golf course. ... If you're hitting the ball well enough, you can definitely run away with it. At the same time, you have to know par is a good number and keep grinding away."
Right behind was Wie, who studied as hard for Pinehurst as she ever did at Stanford. She was at Pinehurst on Sunday to watch the final round, and later picked up the yardage books from a couple of friends in south Florida U.S. Open runner-up Rickie Fowler and Keegan Bradley and compared notes.
Wie charted her way to four birdies on the back nine for a 68.
"I did a lot of homework," she said. "Just took the notes from both of the books. It really helped just because they played last week in similar conditions. And they're obviously great players. I definitely learned a thing or two."
Her putter certainly helped. Wie rolled in long birdie putts at Nos. 12 and 14, made a good par save after going into a bunker on the 17th and hit her approach to 5 feet on the final hole. It was her lowest opening round in a U.S. Women's Open. She had started with an 80 or higher four of the last six years.
They were among only five players under par when the first round was halted by thunderstorms with 30 players who did not finish.
Brendan Steele shot an 8-under 62 to take a one-stroke lead after the first round of the Travelers Championship in Cromwell, Conn. The 31-year-old Californian opened with an eagle, holing a 129-yard wedge shot in the rain.
He birdied six of the next 12 holes at TPC River Highlands, and closed the bogey-free round with five straight pars.