The slippery conditions limited UNC's usual speed attack led by forwards Chris Carrieri and Caleb Norkus.
Instead, it was the Tar Heels' height that was the major factor in the victory. UNC headed in all three goals off reset plays that resulted from fouls or corner kicks.
"North Carolina has a very big team," William & Mary coach Al Albert said. "It was just a little bit too much size for us to handle."
Carrieri did have an impact in the game-winning goal in the fourth minute of the overtime. After his corner kick got blocked out of the box, he recovered the loose ball and sent another cross into the box.
This time, forward Ryan Kneipper got his head on the ball and deflected it down and into the right side of the net.
The Tribe almost stole the victory earlier in the overtime period off a free kick. Midfielder Kris Feldman headed the kick from the edge of the 18-yard box, but it hit the goal post.
UNC got into the overtime period as a result of the play of midfielder Matt Laycock.
Trailing 1-0, Bolowich substituted in the 6-foot-5 Laycock in the 60th minute to give the Tar Heels another tall body in front of the goal on crossing opportunities.
William & Mary increased its lead to 2-0 with a headed goal by Phillip Hucles off a free kick.
Two minutes later, Laycock got his first goal off a served ball by Danny Jackson on a free kick. Laycock jumped above the crowd to head the ball into the right side of the goal.
"(Laycock) really changed the game a little bit," Albert said. "In the first half, we were having trouble with the balls into Bucy's head, and that was OK. But when the second big guy came in, it really was tough for us."
Laycock rose above the crowd again in the 72nd minute to tie the match 2-2. This time Laycock headed a Matt Crawford cross into the right side of the net. Carrieri also got an assist.
"I've also got to give our team a whole lot of credit because we were the ones that were 2-0 down," Bolowich said. "We were the ones that had to dig a little bit deeper. We were the ones that were about to lose their spirit after the second goal, but it did not happen."
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