USGA photo

Peck, a candidate for Junior Player of the Year in the U.S., squeaked by Boom Sritart of Keller, Texas, in the second round before coming on strong in the afternoon for a big win over Rak Cho of Korea, 7 & 5. Grillo, already the top-ranked amateur in Argentina, had an easier time of it. He scored wins by margins of 4 & 2 over Bryden Macpherson of Australia and 6 & 5 over Robert Galbreath of Huntingdon Valley, Pa.

Play continues Friday with the quarterfinal and semifinal rounds of match play. The 36-hole championship final is scheduled for Saturday.

“I played better than yesterday, but I will have to play well again tomorrow,” said Grillo, who will be a high school junior.

At the North Open in Argentina in May, Grillo finished tied for second place with Angel Cabrera, one stroke behind winner Eduardo Romero.

In the same bracket, Andrew Steinhofer, 17, of Madison, Wis., will meet Dom Bozzelli, 17, of Pittsford, N.Y. Steinhofer rallied to edge local favorite Tom Lovelady of Birmingham, 1-up in the third round. Bozzelli reached the quarterfinals with a victory over Gaston De La Torre of Brush Prairie, Wash., 3 & 2.

Fourteen-year-old Jordan Spieth of Dallas, Texas, stole the show in the other bracket. He needed to play just 28 holes in beating accomplished junior player Julian Suri of St. Augustine, 4 & 3, and David Persons, 8 & 7. He won seven of the first eight holes against Suri and was four under on the first nine holes.

“All of a sudden I was four up and he wasn’t really playing that bad,” said Spieth, who will be a sophomore in high school. “I thought, ‘Wow! Maybe today is my day.’”

He will face Andrew Yin, 17, of Chandler, Ariz., who stopped top-seeded Jorge Fernandez Valdes of Argentina. He ended Fernandez Valdes’ run in the third round. He rallied to win holes 17 and 18, and then made a winning par on the third extra hole.

“I am mentally drained, but I am very excited by coming through when I was down against a great player,” said Yun, who moved to Arizona from Tacoma, Wash., two years ago. “I’ve had to play a lot of good players just to make it this far.”

In another matchup, Evan Beck, 17, of Virginia Beach, Va., will face Ernesto Marin, 17, of Miami, Fla.

Beck beat J.J. Spaun of San Dimas, Calif., to reach the quarterfinals, 3 & 2. Marin beat T.J. Vogel of Miami, Fla., 4 & 2.

“It was just my day,” said Beck, a sleek 145-pounder who didn’t three-putt in either of his two matches Thursday. “I switched to the claw grip in May and I’ve been putting well ever since.”

All eight quarterfinalists are fully exempt for the 2008 Junior Amateur if they are still age 17 or younger.

The U.S. Junior Amateur is one of 13 national championships conducted by the United States Golf Association, 10 of which are strictly for amateurs.

--Courtesy USGA

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