Creighton doesn't have a single win this season against a top 100 RPI team.
Yep, thats why RPI is discounted come selection Monday time. Its fun to follow, but not near the tool it is for College Basketball. I've followed college baseball long enough to know that an RPI will keep you out of the tourney, but definitely not get you in. To me, Nebraska's resume is far, far more complete then Creightons, and Nebraska is not an at large team at this point.
Creighton does still have some high RPI teams left, including 3 at BYU in a couple of weeks, but otherwise they are where Nebraska is: Win the conference tourney to get in.