(Reuters) - Lydia Ko had her putter to thank for keeping her in the hunt for a third straight major on Friday after the world number one shot a one-under 70 that left her a stroke behind leaders Brooke Henderson and Lee Mi-rim at the KMPG Women’s PGA Championship.

Ko scrambled her way to eight pars and a birdie on the back nine of her second round at Sahalee Country Club outside Seattle. South Korean Lee had a 69 while Canadian Henderson had a two-over 73.

“If it wasn’t for my putter I know I wouldn’t be in this position,” said Ko, who won the Evian Championship in September and the ANA Inspiration in April.

“I feel like I’m in really good position. There’s still a lot of golf to be played, I just have to focus on my game and enjoy it rather than think about what could happen on Sunday.”

First-round leader Henderson looked like she would again finish the day alone in top spot but her second into the 18th found a bunker and she made bogey to drop into a tie with Lee.

“I’m disappointed with the missed (par) putt at the last but overall I’m happy with where I am,” said the 18-year-old.

“It was a tough day and the conditions made it difficult. I hung in there.”

Early sunshine gave way to cool temperatures and eventually rain.

Lee enjoyed one of the day’s best rounds with a two-under-par 69 that took her to the top. Ko has Gerina Piller and Brittany Lincicome for company in third spot.

Piller, who has finished in the top three in three of her last five events, was unhappy with her ball-striking on Friday.

“I just knew that I was going to probably hit some squirrelly shots, but if I can kind of keep it in front of me and if I'm out of position, and get back in position,” Piller said.

“I'm putting great, so I know if I can just get around the hole I have a chance to make par or birdie or save some shots there.”

Japan’s Ai Miyazato shot a one-under 70 playing alongside Henderson and is two shots back at even-par with Tiffany Joh, Australian Su Oh and South Koreans Ryu So-yeon and Kim In-kyung.

(Writing by Jahmal Corner in Los Angeles; Editing by Peter Rutherford)