Smith bounced back from a toe injury suffered in Friday's quarterfinals win over Maryland, handing out six assists and sparking the Blue Devils (29-4) to a Sunday appointment with the Tar Heels for the ACC crown.
Kyle Singler added 13 points and 11 rebounds for Duke, who will face the rival Tar Heels in an ACC championship game for the first time since 2001.
The Hokies (21-11) were led by Malcolm Delaney with 19 points and also got 17 from Erick Green.
Virginia Tech was held to 2-of-16 shooting from beyond the arc.
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