To get the second half of their season started on a high note, the Huskers will need a much-improved performance from their much-maligned defense. When Nebraska takes on Northwestern on Saturday they’ll have to cope with the Wildcats’ speedy backfield of quarterback Kain Colter and running back Venric Mark. Colter’s more than a quarterback in the Wildcats attack – he’s lined up as a wide receiver and been a favorite target of backup quarterback Trevor Siemian. Last season, Colter came up large for the Wildcats in a 28-25 upset of the Huskers in Lincoln, throwing two touchdown passes and rushing for a score. Husker defensive coordinator John Papuchis told the press after yesterday’s practice that there’s no denying that stopping Colter is the main goal of his unit. Saturday’s game at Ryan Field kicks off at 2:30.