one loss to a really good team is not reason enough to cause alarm... agreed.
But... losing 3 of the last 4 games last year --- all the losses being attributable to NU lack of preparation/focus and/or implosions coupled with...
4 non-conference games this year (victories, yes) but without a single game where the O and the D played with intensity, played focused or played well for more than perhaps a quarter or two per game, coupled with...
a blowout loss to a good team --- but in which NU looked beyond bad for big portions of the game, coupled with...
a team that 4 years in to the Pelini era should be competitive (defined as being able to compete with top 5 or, at least, top 10 teams w/o getting embarrassed) and getting better but is not competitive (we get laughably smoked by top competition) and is not getting better, coupled with...
player attitude problems, and recruiting that is progressing somewhat.... slowly AND...,.
all these things together are reasons for concern --- the latest blowout loss on national TV is not alone as an indicator of "reason for concern" --- it is, however, certainly consistent with these other indicators that things are not going well for Big Red. The arrow is doubtless pointing, at least for the moment, in the wrong direction.