DUBLIN, Ohio (Ticker) -- Scotland's Mhairi McKay was not allowed to play her home course this week. But she looked right at home at the Tartan Fields Country Club.

McKay fired a bogey-free 7-under-par 65 on Friday for a one-shot lead after the opening round of the Wendy's Championship for Children.

With the LPGA Tour set to play the Women's British Open at Turnberry Golf Club, McKay was kept off the course she has played since she was 10.

"The weather is so unpredictable over there, I felt my time would be just as well spent competing and working my game in good weather here," McKay said.

In steamy conditions, the 27-year-old Glasgow native collected an eagle and five birdies for a one-stroke lead over Rosie Jones, who finished fourth here last year.

"Oh, I'm drained," said McKay, who is seeking the first win of her five-year career. "It's exhausting out there. The heat and humidity really takes it out of you. I'm just glad to sit down for a few minutes. But I'm ecstatic with the way I played. I struck the ball really well and managed to make some putts, so I'm delighted."

The conditions were even tougher on Jones, who has been battling a cold.

"I think I was fried before the 18th, before I started," she said. "This cold has kind of knocked me out, kind of unexpected. All of a sudden, I got here this week and got really sick. I was feeling really bad yesterday, but I think I'm on the upswing now."

Also on the upswing was unheralded Michele Vinieratos, who shot a 67 on her 34th birthday for sole possession of third place.

"I was looking forward to today. Today is my birthday," said Vinieratos, an American citizen who was born in Germany. "I hit it well. Things started going well. Putter was rolling well. Birdies started falling."

The birdies started falling early for McKay, who started on the 10th tee and rolled in putts of 20 and 10 feet at the 11th and 12th holes, respectively. At the 503-yard 13th, she left a 3-wood just 10 feet from the cup to set up an eagle that rocketed her to 4-under.

After five straight pars, McKay chipped to set up another 10-foot birdie at the 546-yard second hole and capped her best round of the year with an 18-foot birdie at No. 8.

"I feel good about my game," she said. "Hopefully, I can reproduce that ball-striking tomorrow. Any score in the 60s, any day, I'm delighted with that. I'm especially delighted with the 65 today."

Defending champion Wendy Ward managed just an even-par 72 and trails McKay by seven shots.

Last year, Ward set a tournament record with a 54-hole total of 21-under and defeated Annika Sorenstam and Moira Dunn by three strokes.

Coming off a playoff win at last week's Big Apple Classic, Korea's Gloria Park struggled to a 77 and already is 12 shots off the pace.