NDSU has won 10 games against teams with records above .500. Those games are Western Michigan, Bryant, Notre Dame, Delaware, Towson, Utah Valley, IPFW, South Dakota State, IPFW, South Dakota State, IPFW. They beat IPFW and South Dakota State twice So they have beaten 8 teams that are above .500. Bryant is a D-II. So they have beaten 7 teams with records above .500 in D-I basketball. I don't think any of those teams made the Tournament.
What type of a melt down would occur if OU lost to any of those teams with the possible exception of Notre Dame? For example, Delaware is a solid team but nobody would say it is acceptable for OU to lose to Delaware.
Oklahoma has beaten Mercer, Tulsa, ISU, OSU, OSU, Texas, Texas, KSU, Baylor, Baylor, that are in the Tournament. OU also beat WVU, TAMU CC, A&M with winning records. Tech, Alabama and Seton Hall did not have good records this year but I suspect all 3 would win NDSU conference or be extremely competitive in that conference.
OU will need to play a solid game but OU should win this game.
I don't mean any disrespect to NDSU. They had a good season and are a solid basketball team but there is a reason OU is a 5 seed and they are a 12 seed.