"I have resigned as head coach at Nebraska to pursue another head coaching job," said Iba, who has just completed 6 seasons at Nebraska after serving 4 as coach at Memphis State. "I resigned immediately after the game and that is all I care to say about the matter at this time."
Ray Swogger scored 16 points to lead a balanced attack and Western Kentucky survived a late rally by the smaller Nebraska team to win.
Western Kentucky, of the Sun Belt Conference, improved to 23-7 and faces the winner of Friday night's Kentucky-Davidson matchup in the second round Sunday. Nebraska, of the Big Eight, finished at 19-11 after its first-ever berth in the NCAA Tournament.
The Hilltoppers pounded the ball inside during a 16-4 second-half spree and led by as many as 18 points, but the Cornhuskers drew within 4 in the final minute. Western Kentucky sank 8-of-8 free throw attempts in the last 53 seconds, including six from James McNary, to ice the victory.
In other first-round Southeast Regional games, No. 20 Illinois downed Fairfield 75-51 to set up a second-round clash with No. 19 Alabama, a 97-80 victor over Xavier.
Western Kentucky played away from its distinct size advantage over the Cornhuskers in the first half, relying on a three-guard offense and perimeter shooting in assuming a 33-26 lead at the break. Swogger ended the half with a pair of jumpers.
The Hilltoppers pushed the ball inside at the outset of the second half. Kannard Johnson and Clarence Martin each tallied 6 points to ignite the 16-4 streak, resulting in a 49-32 lead with 13:19 remaining in the game.
Bernard Day scored 8 points, including two three-point plays, and Brian Carr and Chris Logan both added 4 during a 20-6 Nebraska surge that trimmed the lead to 59-55 with 1:34 remaining.
Billy Gordon scored 12 points and Martin added 11 for Western Kentucky. Day paced Nebraska with 18 points.