Mac Hopson scored 16 points, including going 12-for-12 from the line, as Idaho fought off Eastern Oregon 82-77 on Saturday night.
The Vandals (6-3) led by as many as 19 points early in the second half and held on with the help of Hopson and Marvin Jefferson, who each scored 10 points in the half.
Jefferson finished with a double-double, scoring 14 points and grabbing 11 rebounds. The Vandals shot 55 percent from the field.
The Mountaineers (7-5) brought the score within six points with about a minute and a half to go. But they couldn't tighten it any more, trading shots with Idaho until Jacques Wilson hit a 3-pointer at the buzzer to bring the deficit to five. By then, it was too late.
Dan Stafford led the Mountaineers with 24 points while Jordan Gregg and Josh Landsverk each added 10.