DURHAM, N.C. - Grayson Allen scored all 21 of his points in the first half, and No. 6 Duke beat Appalachian State 93-58 on Saturday.
Luke Kennard added 18 points and Amile Jefferson and Frank Jackson each finished with 15 for the Blue Devils (6-1).
They will bring a four-game winning streak into their visit from No. 24 Michigan State on Tuesday night.
Kelvin Robinson scored 12 points for the Mountaineers (2-3), who average 89 points but for the first time were held to fewer than 70.
Allen, who has been playing through a right foot injury suffered in last week's loss to No. 5 Kansas, appeared to tweak that foot or ankle when he went down while going for a rebound with about 12 minutes to play and Duke leading by 35. He stayed on the bench for the rest of the game.