North Carolina rallied after falling behind by two goals, and Duke, Maryland and Florida State eked out victories as the Atlantic Coast Conference tournament opened at SAS Stadium in Cary, N.C.

The top-ranked Tar Heels improved to 19-0-0 with a 6-2 victory over tournament host North Carolina State after trailing, 2-0, by the 18th minute.

No. 10 Duke rallied to beat eighth-ranked Virginia, No. 9 Florida State topped Wake Forest, and Maryland upset No. 12 Clemson, all by 2-1 scores, in the other quarterfinals.

Tournament action took place in four conferences, with Marilyn Marin — the top scorer in NCAA Division I a year ago — netting her 20th, 21st and 22nd goals of the season in North Texas' runaway victory in the Sun Belt quarterfinals; two Conference USA quarterfinals decided on penalty kicks and another on a goal deep in overtime; and Brigham Young moving closer to another showdown with Mountain West champion Utah.

At Cary, Erin Griswold's 10th goal of the season, on a sixth-minute breakaway, and Lindsey Underwood's 18th-minute strike off a throw-in pushed North Carolina State (9-9-1) ahead of the nation's top team.

Carolina rallied to tie the score by halftime, on goals by Heather O'Reilly and Lori Chalupny, then pulled away on Lindsay Tarpley's 19th goal of the season, in the 56th minute, and goals three minutes apart by Kacey White and Mary McDowell, in the 67th and 70th minutes. Anne Felts added the sixth six minutes later.

Tarpley, Chalupny, White and McDowell also contributed assists for the Tar Heels.

Leah Gallegos' 15th and 16th goals of the season carried Florida State (12-6-1) past Wake Forest; Duke (13-5-2) got second-half goals from Darby Kroyer and Gwendolyn Oxenham to top Virginia; and Kimmy Francis scored a pair of goals to lift Maryland (11-7-1) past Clemson.

In other conference tournaments:

Conference USA: Top-seeded UAB needed penalties to reach the semifinals, but second-seeded TCU was beaten on spot kicks. UAB (13-4-1) outfired host Charlotte, 3-1, after a 1-1 tie. Jenny Rynders gave the Blazers an early lead, but 2002 All-American Courtney Crandell pulled Charlotte even with one second remaining in regulation. In Thursday's semifinals, UAB will meet St. Louis (13-5-2), a 2-0 winner over South Florida as Jamie Perry scored a goal and assisted another. Tulane (11-6-2) topped TCU, 3-0, after a scoreless draw and will meet DePaul (13-6-1), which surprised third-seeded Marquette, 2-1, on Erin Walter's 107th-minute goal.

Mountain West:Krissa Campbell and Lydia Ojuka assisted each other's goals as second-seeded Brigham Young (13-5-2) dominated Air Force, 2-0, in the quarterfinals at Rice-Eccles Stadium in Salt Lake City. The Cougars advance to Thursday's semifinals against New Mexico (3-11-4), which upset third-seeded Wyoming, 2-1, in overtime. Coco D'Angelo's 107th-minute goal was the difference. No. 15 Utah, the top seed, begins action Thursday against UNLV (9-9-2), which got goals from Kim Egertson and Kim Chock in a 2-1 win over San Diego State.

Sun Belt: Marilyn Marin's 11th career hat trick and Melissa Chapman's first carried second-seeded North Texas (14-5-1) past Arkansas State, 10-1, and into a semifinal matchup with Middle Tennessee State (12-6-2), a 3-0 winner over UA Little Rock. Top-seeded Denver (16-3) romped, 5-0, over UL Lafayette as Jenni Harris had a hat trick and will meet Western Kentucky (11-5-2) on Thursday. Jenny Dalby assisted early goals by Crystal Chapon and Jocelyn Roach in the Hilltoppers' 3-2 win over South Alabama.