Nebraska won't be able to control the line of scrimmage like Wisconsin did on both offense and defense. Nebraska's defense is solid, but struggles at generating pressure and causing turnovers. If they can't get pressure on AOC, then Purdue's offense will look more like the Iowa game compared to Wisconsin.
I think Purdue's defense matches up well against Nebraska's offense. Nebraska's offensive line is nowhere near Wisconsin's run blocking ability, and struggles even more than Wisconsin in pass blocking.
RB Rahmir Johnson catching passes out of the backfield, TE Austin Allen, a second TE set with Vokolek, or Martinez making plays with his feet could create problems for Purdue's defense. So, Graham and Grant will need to have a big game. Nebraska will probably want to game plan like Minnesota, where they go for big plays on double moves or other methods to create separation on an aggressive defense.
If Purdue's defensive line can control the LOS, then that will force Nebraska into a lot of 3rd and long situations. You have to like Purdue's chances on getting pressure on those types of situations to force Martinez to make mistakes.