Olsen scored 17 points, including three 3-pointers.
“That is a tough one, we had lots of chances," said Utah State head coach Stew Morrill. "Those are hard games to lose. We battled hard and gave ourselves chances. We just couldn’t get over the hump.
Denver (16-8, 12-2 Western Athletic) had three other players score in double figures. Royce O'Neale had 14 points, Chase Hallam had 13 and Chris Udofia had 10. Hallam had two 3-pointers.
Denver won despite being outmuscled on the boards 36-19.
Utah State (17-6, 8-5) was led by Jarred Shaw, who scored 18 points and grabbed nine rebounds.
Spencer Butterfield scored 16 points and Ben Clifford scored 14.
“This is the second time that that has happened to us this year," said Shaw. "It is a tough way to lose after we fought our way back into the game. We can’t hold on to this for very long, we have another game Saturday.
Utah State shot seven 3-pointers, making only one. And the Aggies only converted 13 of 21 free throws.
The Aggies next host New Mexico State Saturday night at 9:00 p.m.