CAMBRIDGE, ONTARIO (REUTERS) - Canadian Alena Sharp called a penalty on herself during the second round at the Manulife LPGA Classic but still managed to grab a share of the halfway lead in Cambridge, Ontario on Friday.

She said the infraction happened after her ball had stopped in short grass, hard up against a collar of rough next to the third green at Whistle Bear.

"When I addressed my chip shot, the ball moved," she told reporters. "I don't think I completely grounded my club, but the way the rule reads, I was going to ground my club and the ball moved.

"I needed to call it on myself because I was going to be thinking about it all day. Two dimples, but it moved. I'm totally all about the rules and etiquette and I just would never not call it on myself when the ball moves like that."

After summoning a rules official to confirm the one-shot penalty, Sharp duffed her chip and made a double bogey but she put the incident behind her to birdie the next hole en route to a six-under 66.

Sharp, who is still seeking her first LPGA victory, ended the day tied with American Lexi Thompson and South Korean Kim Hyo Joo at 12-under 132, one stroke clear of three others on a crowded leaderboard.

The long-hitting Thompson made seven birdies, including four in a row from her second hole, on her way to a flawless 65, while Kim also had seven birdies in a 67.

First-round leader Suzann Pettersen had a 71 to total 135 while Lee Mi Hyang, who had tied Pettersen after the first day, had a 72 to lie one shot behind. World No. 2 Ariya Jutanugarn carded a 70 to lie on 137.