Cory Raji's two free throws 1:03 into overtime gave BC a 68-66 lead, but the Hokies scored the next seven points. Thorns pushed Virginia Tech in front for good with a 3 from the left wing and followed with a breakaway layup that made it 73-70. Washington then scored in the lane.
The Eagles closed to 73-70 on Shamari Spears' putback, but Thorns made two free throws that pushed the Hokies ahead 77-71 with just over a minute left.
Virginia Tech led 41-33 at halftime.
The Hokies played without second-leading scorer Jeff Allen, who served the final of his league imposed two-game suspension for inappropriate contact with a referee during last Saturday's game against Georgia Tech.
Oklahoma State basketball player Tyrek Coger died after a 40-minute team workout on the football stadium stairs in hot weather, university officials said Friday.
Prospective NCAA championship host cities must identify local anti-discrimination laws in a questionnaire being sent out by the college sports governing body.
The Class of 2017 is full of talented big men, but Richards is getting noticed by more programs during the current evaluation period in Las Vegas.