Martin, while arguing with a referee about the length of Wake's passes, did not cover her opponent on the outside of the circle.
During Martin's brief, but heated, conversation with the ref, Deacon Jennie Shelton was able to get open in the circle and blast a right- side, 12-yard score to give Wake an early lead.
"(The goal) just shows me to keep my mouth shut or the worst can happen," Martin said.
After Wake's Kelly Doton scored off a penalty corner with 25 minutes remaining, UNC began to wake up from its offensive doldrums.
Shelton called a timeout to recharge her troops, something her players claimed rubbed off on them on the field.
"When Karen called that timeout, she was pumped," said senior Susan Hayes. "It's really inspiring though, because she puts her whole heart into it."
With 15 minutes left in the contest, freshman Kerry Falgowski recovered a rebound off an Abbey Woolley shot and pushed home a seven-yard shot that cut the lead in half.
UNC wasn't settled quite yet.
With five minutes remaining in regulation, Martin rebounded nicely from her earlier lapse when she knocked home a left-side goal on a penalty-corner option.
Suddenly, Wake's control of the contest had shifted in UNC's favor.
"It was a great game with the shift of momentum," said Wake coach Jennifer Averill. "Two-zero isn't good enough. I wanted a three-, four-, maybe five-goal lead with five minutes left."
But after exerting its energies to tie the game, UNC fell flat in the overtime period and suffered its third OT defeat in as many contests in 2001.
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Off a penalty-corner option, Deacon Lucy Shaw blasted the game-winning shot from 15 yards out. The shot, Wake's 19th of the game, set off a frenetic celebration on UNC's home field.
After the loss, the Tar Heels will now await word on Tuesday for their seeding in the NCAA Tournament.
The fourth-ranked Tar Heels hope the loss to Wake won't drop the team below their current ranking.
The Tar Heels will wait to see if No. 5 Michigan's 3-0 loss in the semifinals of the Big Ten tournament is enough for UNC to maintain its No. 4 ranking. If so, the Tar Heels would take on their NCAA tournament opponents next weekend at home.
"The encouraging thing is that I think my team is improving," Shelton said. "We are making progress and I still firmly believe we are one of six, seven, eight teams in the country that can win the national championship."
The Sports Editor can be reached at sports@unc.edu