The 12-year-old, home-schooled seventh-grader from Coral Springs, Fla., already the youngest qualifier in U.S. Women's Open history and the recent Junior PGA champion, beat Pearl Jin 5 and 4 today in the second round at Crooked Stick Golf Club.

Thompson and Jin, also 12, were the youngest qualifiers to reach match play in the Women's Amateur.

Thompson birdied three of the first six holes, including a 7-foot putt on the par-3 No. 6, and went 5-up after eight. They halved the next six holes to finish the match, sending Thompson to the next round against 18-year-old Lizette Salas of Azusa, Calif.

Thompson later defeated Salas, 5 and 4.

"It's a great experience," Jin, of San Gabriel, Calif., said of the preteen matchup. "My swing was off today. I didn't hit the ball solid, and my putts just didn't go in. I was nervous today. It affected my swing and my putting rhythm and tempo."

Salas advanced to the third round by beating Kira Meixner of Canada in 19 holes.

Also eliminated in the second round was co-medalist Kristina Wong of Vestal, N.Y., who was beaten by Vicky Hurst of Melbourne, Fla., 3 and 1. The other co-medalist, NCAA champion Stacy Lewis of Arkansas, lost in the first round yesterday. No medalist has won the women's amateur since Meredith Duncan in 2001.

Other second-round winners included Amanda Blumenherst, a Duke junior and 10th-place finisher in the U.S. Women's Open last year, who beat Jenny Suh of Fairfax, Va., 5 and 4.