Armstead scored 21 points and had six assists, and Dunigan had 20 points and 14 rebounds for the Ducks (10-4, 2-0 Pac-10). Tajuan Porter added 16 points.
The Huskies led 29-21 in the first half, but the Ducks used an 11-2 run to go up 32-31 and they took a 42-41 edge into the break.
Oregon took control in the second half. A baseline jumper by Armstead less than 3 minutes into second half made it 50-42 Ducks and Oregon led 76-61 with 6:42 remaining on a Teondre Williams 3-pointer.