Michigan State athletic director Mark Hollis says his peers in the Big Ten are comfortable exploring the possibility of a four-team playoff for the national championship.

Hollis says keeping ties to the Rose Bowl is extremely important to athletic directors in the Big Ten and Pac-12.

The Chicago Tribune reported Monday that 1 of the ideas before the Big Ten would put the two semifinal games on the campuses of the higher seeded teams. The national championship game would be awarded to cities that bid for it.

The BCS title game pits the nation's top two teams based on poll and computer rankings.

The plus-one format -- two semifinals plus the title game -- was proposed in 2008 by the commissioners of the Southeastern Conference and Atlantic Coast Conference. It was shot down by the leaders of the Big Ten, Pac-10, Big East, Big 12 and Notre Dame.