Published: Jul 29, 2011 1:43 PM EDT
Updated: Jul 30, 2011 6:30 AM EDT

CARNOUSTIE, Scotland (AP) - Germany's Caroline Masson shot a bogey-free 65 to take a surprise lead after the second round of the Women's British Open on Friday.

Playing in the last group out, the 22-year-old Masson bagged seven birdies to move 11-under at 133, one stroke clear of South Korea's Inbee Park and Meena Lee.

Masson, competing in only her second season on the European Tour, had four birdies in a front-nine 32.

"Unbelievable right now," was Masson's reaction after her round. "I've just had two great days out there and I'm very happy to be playing so well.

"I've played really solid, hit the fairways, hit the greens and made some putts. It's been awesome."

Park racked up nine birdies and dropped just one shot in a 64, while overnight leader Lee added a 69 to her opening 65 after closing with two birdies.

"It was a very solid day," Park said. "I putted pretty good out there and hit it really good, so I'm looking forward to the next two days."

Three players are on 8-under, Dutchwoman Dewi-Claire Schreefel and two other South Koreans, Ser Ri Pak, who hit eight birdies in a 64, and Na Yeon Choi.

Top ranked Yani Tseng from Taiwan, the defending champion, is just four off the pace after adding a 66 to her opening 71 with six birdies an eagle and two bogies.

"I'm very happy with the position I'm in," she said.

Brittany Lincicome is the highest placed American on 6-under 138 but she was disappointed with her round of 71.

"I just couldn't get anything going today. I had 32 putts out there, which means I wasn't hitting my second shots close enough, or I just wasn't making anything," she said. "But I'm happy with where I am going into the weekend."

Alongside Lincicome are Sweden's European Tour rookie Caroline Hedwall, who shot a second consecutive 69, Japan's Mika Miyazato and another South Korean, Amy Yang.

A further stroke back in a group on 5-under is Paula Creamer, who added a 70 to her opening 69.

"If I just go out and make as many birdies as I have been and eliminate the bogies then I feel I'll be right there on Sunday," Creamer said.

Perhaps the unluckiest player of the day was fellow American Angela Stanford, who is on 4-under after a 72 but who could have been two better but for a bizarre incident at the final hole.

A steward indicated that her second ball had gone out of bounds, so she played another but didn't declare it 'provisional'.

Her first ball had been kicked back in-bounds when she got to it, but it was too late as her second ball, not being declared 'provisional', was now the ball in play. So she was on the green in four and two-putted for a six.

"I learned something today," Stanford said. "I didn't think I had to ever say provisional, but I guess you always say provisional."