Ariya Jutanugarn

Jutanugarn, playing in her third Junior PGA Championship, used a second-round 70 for an 8-under-par 136 total, and leads Samantha Wagner of Windermere, Fla., who shot 71.

McDaniel, who won the 2012 PGA Junior Series event at Kearney Hill Golf Links in Lexington, Ky., to qualify for the Championship, shot a 69 for a 7-under-par 137 total. Jim Liu of Smithtown, N.Y., the top-ranked junior boy according to Golfweek's latest rankings, is second at 138.

The 72-hole Championship, being staged for the third consecutive year at Sycamore Hills Golf Club, features a 54-hole cut to the low 30 boys and 30 girls, including ties, following Thursday's third round.

Jutanugarn, winner of this year's Canadian Women's Amateur, played her first nine holes in 2 under par.

"I played well at the start of my round," said Jutanugarn, who owned a one-stroke lead heading into the second round. "I made birdies and hit my irons pretty good."

She struggled on her back nine, making three bogeys over her final nine holes.

"At the end of the round, I didn't hit my irons good," said Jutanugarn. "I would hit it 10 yards over one green, and 10 yards in front of another. I need to improve."

Wagner, a 2015 high school graduate who has already verbally committed to the University of Florida, was able to steady herself after a double bogey on the par-5 15th, her sixth hole of the day.

"I was struggling on the front nine and just overall I wasn't that steady," said Wagner. "But I am pretty happy and the round could have been a lot worse than it was."

Alison Lee of Valencia, Calif., fired a 67, the low round of the day in the Girls' Division, to jump into third place, four strokes off the pace. After an opening-round 73, Lee bounced back with a bogey-free second round that included five birdies.

"All my shots were working today. I was hitting everything on the green and gave myself chances," said Lee. "I'm not too far behind, [Ariya Jutanugarn] and there are two rounds left. If I continue to play well, I hope to be close at the end."

In the Boys' Division, McDaniel, 16, had three birdies to offset a single bogey and shoot a second consecutive round in the 60s.

"Today I just played solid from tee to green," said McDaniel. "I have my putter going so well so far. It's saved shots, its given me scoring opportunities and that's what you need to win."

McDaniel also credits his solid play to a tip he heard during Davis Love III's keynote speech on Monday at the Junior PGA Championship's opening ceremony.

"Mr. Love said earlier this week that you have to take this game one shot at a time and you can't get ahead of yourself," said McDaniel. "I have been doing a great job of that this week. But I need to continue to do that and put myself in a position to score over the final two days."

Liu, who played a bogey-free golf for 17 holes on Tuesday, made his only error on his final hole of the day, the par-4 ninth.

"I hit a bad tee shot on my last hole, followed it up with a bad approach and then missed a short putt for bogey," said Liu. "The rest of the week, if I get any bad breaks like this, I need to keep a positive attitude and put myself in a position to win."

Rylee Reinertson of Gibbon, Neb.; Cameron Champ of Sacramento, Calif.; and Rhyne Jones of Blowing Rock, N.C., are tied for third at 139.

Beau Hossler of Mission Viejo, Calif., who opened with a 68, struggled to a 77 as in a tie for 16th.

This year's field includes past winners of the Championship, PGA Junior Series event champions, PGA Section winners, many of Polo Golf and Golfweek's top-ranked players, and selected national junior tournament winners.

Golf Channel will present a one-hour highlight show of the 37th Junior PGA Championship, with the first airing on Mon., Sept. 17

Begun in 1976, the Junior PGA Championship has traditionally produced unforgettable golf performances and brings together the best junior golfers from around the country to compete for the Jack Nicklaus Trophy in the Boys' Division and the Patty Berg Trophy in the Girls' Division.

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