Battle of defenses: No. 13 Northwestern vs No. 18 Michigan

ANN ARBOR, Mich. (AP) Northwestern and Michigan have made steady climbs up The Associated Press poll due to their defenses.

The 13th-ranked Wildcats have shut out two teams and are giving up a nation-low seven points a game. That has helped Northwestern equal its total number of victories in each of the previous two years. If the Wildcats win Saturday at the Big House, they will be 6-0 for the first time since 1962 when Ara Parseghian was their coach.

No. 18 Michigan, meanwhile, is a win away from matching the number of victories it had last year in Brady Hoke's final season before being fired.

The Wolverines have blanked consecutive opponents, rank first in third-down defense and second in points allowed under Jim Harbaugh.