Semple Thompson, who owns two Women's Mid-Amateur titles, beat Marianne Towersey, 5 and 4, in a second-round match, but then lost to Meghan Bolger, 6 and 4 in the afternoon at Old Waverly Golf Club.
Two other past Mid-Am champions remaining in the field advanced to quarterfinal play. Virginia Grimes, the 1998 winner and a 2006 USA Curtis Cup player, upended Lisa Smego, 4 and 3, in the second round and then topped Rheba Mabie, 4 and 2, in the third round. Ellen Port, a three-time Mid-Am winner, routed Lori Planos, 6 and 5, in the second round and then beat Benedikte Brynestad Grotvedt, 4 and 3, in the third.
Grimes will play Laura Coble in the quarterfinals Wednesday, while Port takes on Jill Hardy. The other two quarterfinal matches will have Marilyn Hardy playing Meghan Bolger and Mari Miezwa facing Thuhashini Selvaratnam.
Quarterfinal and semifinal matches will take place Wednesday, while the championship match will be held on Thursday.
Stroke-play medalist Dawn Woodard lost in the second round of match play to Marilyn Hardy on the 20th hole.
The U.S. Women's Mid-Amateur is open to female amateur golfers who will have reached their 25th birthday on or before October 21, 2006, and who have a USGA Handicap Index not exceeding 9.4.
Last year, Mary Ann Lapointe defeated Kerry Postillion, 1-up at Shadow Hawk Golf Club in Richmond, Texas.