Springfield, IL (My Sportsbook) - Cristie Kerr's mission Saturday was to put herself in contention at the LPGA State Farm Classic.

Despite making back-to-back bogeys down the stretch, Kerr accomplished what she set out to do by shooting a six-under 66 to share the third-round lead with Kristy McPherson (69).

The co-leaders finished 54 holes at 12-under-par 204, a stroke ahead of South Korea's Jiyai Shin (69).

Hall of Famer Se Ri Pak (72) leads a seven-way tie at 10-under 206 that also includes Ai Miyazato (65), Angela Stanford (69), Helen Alfredsson (71), Amy Hung (69), In-Kyung Kim (69) and Pak's fellow second-round leader, Suzann Pettersen (72).

Kerr was on cruise control until she hit a fairway bunker at No. 16 on the way to her first bogey in 21 holes. She missed a seven-foot par putt at No. 17 for another bogey.

Prior to those mistakes, Kerr had been eight-under par for the round and enjoying a two-stroke lead. She joked that the last few holes "played a lot tougher than the rest of the course."

"Even shooting however many under (par) I did today, I still learned something coming down the stretch," said Kerr.

Kerr's bogeys gift-wrapped the lead for McPherson, who would experience her own mistakes on Panther Creek's tough closing stretch. McPherson, carrying a two-stroke lead to the 17th hole, finished with back-to-back bogeys to fall into a share of the lead with Kerr.

McPherson hit a stray tee-shot at the par-three 17th, then went long with her approach to the 18th green.

"I'm just glad to be finished. It was tough out there," said McPherson. "I'm not going to go home looking at [the bogeys]."

McPherson, seeking her first LPGA Tour win, collected only seven pars on Saturday. In windy conditions, she scattered seven birdies and four bogeys across the rest of her scorecard in an up-and-down round.

"I made a lot of birdies out there for the conditions we had," McPherson said.

Kerr's round was steadier -- at least until the end. Having an easier time with the wind, she started with an eagle at No. 1 after knocking her second shot to the par five within 30 feet of the hole. Further birdies at three, five and six helped Kerr shoot a 31 on the front side.

"I'm a grinder," she said. "I like the tough conditions."

Kerr made three more birdies at the 11th, 13th and 14th holes, all on putts inside 12 feet. Following her late bogeys, it seemed unlikely that she would hold a lead going into Sunday.

But the 13-time LPGA Tour winner -- she has one victory already this season -- didn't count on McPherson making similar mistakes.

"I went out today with a mission to put myself into contention again," said Kerr. "I did that."