USA TODAY Sports

The last weekend of September puts a fitting end on the first month of college football. There's two huge top 10 showdowns that are certain have an impact on the playoff chase.

Perhaps the biggest game of the Big Ten regular season will take place in State College when No. 9 Penn State hosts No. 4 Ohio State. The past two winners of the conference have staged memorable showdowns in the last two meetings. The winner gets a huge lift in the East Division. The loser will need some help if it wants to keep its title hopes alive.

The other matchup sees No. 7 Stanford visit No. 8 Notre Dame. The Cardinal are fresh off their stirring comeback against Oregon. A win would add a significant non-conference victory to their resume. For the Irish, this shapes up to be the biggest hurdle on their path toward the playoff.

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The other game between ranked opponents sees No. 23 Duke host No. 24 Virginia Tech. This looked to be a meeting of two unbeatens before last week's shocking loss by the Hokies at Old Dominion.

Elsewhere, No. 12 West Virginia get its first Big 12 test on the road at Texas Tech. The Red Raiders will look to continue their momentum after beating Oklahoma State last week.