Bernard Day scored 18 points without missing a shot for Nebraska (18-11). Derrick Vick and Anthony Bailous added 14 points each and Carr scored 12.
Smith paced Marquette (16-13) with 18 points. Johnson came off the bench to add 16. Tom Copa scored 14 and David Boone 12.
Marquette led by 44-38 at halftime.
Washington 98, Montana State 90 - Guard Greg Hill scored 11 of his 26 points in overtime to lead Washington (19-14) to an NIT victory in Bozeman, Mont.
Seven-foot center Chris Welp's 15-foot jumper with 4 seconds remaining in regulation time tied the game at 80-80.
Then the 6-foot Hill took over, hitting a three-point shot with 12 seconds gone in the overtime and adding a 17-footer just 43 seconds later.
Boise State 62, Utah 61 - Reserve guard Mike Sanor's rebound basket with 25 seconds left gave Boise State (22-7) the victory in an NIT game in Boise, Idaho.
With 1 second left, Utah's Albert Springs missed two free throws and Boise State's Greg Dodd grabbed the rebound.
Center Mitch Smith led Utah with 15 points, while Tommy Connor had 13 and Albert Springs 11. Dodd's 15 points led Boise State.