Big Ten power rankings: Week 5

4. Illinois (4-0): There were some tense moments, but Illinois found a way to remain unbeaten and improve to 4-0 for the first time since 1951. It's a significant achievement, and a playmaking defense continues to be the biggest reason for the Illini success. Illinois can't lean on its defense forever, though, and must clean up some mistakes on offense. An inability to convert red-zone opportunities into touchdowns could come back to haunt the Orange and Blue.

espn.go.com