Significant news came out of the Nebraska football team’s practice on Saturday: coach Bo Pelini dismissed Quentin Castille after the running back violated unspecified team rules.

Pelini didn’t elaborate on the situation, but Castille had been absent from practice for the last few days.

“It’s pretty black and white, my expectations and what we lay out as a staff, and if someone doesn’t follow those policies and guidelines, they’re no longer going to be with the program, and that’s the case with Quentin,” Pelini said in a statement.

Troubling news for the Cornhuskers, whose strength this season was supposed to be running the football. Castille and Roy Helu, Jr. formed one of the best one-two running back punches in the Big 12. Now, Nebraska will be forced to insert a freshman — Rex Burkhead — into the No. 2 RB slot.

Castille ran for 467 yards and six scores last season in limited action with Marlon Lucky and Helu also taking carries. Castille displayed what he could do in a full-time role against Clemson in the Gator Bowl, running for 125 yards on 18 carries.

This is very significant. Suddenly, Nebraska doesn’t seem as explosive on offense. Who knows, maybe receivers Niles Paul and Menelik Holt step up, but they’ve only caught one combined touchdown pass. And Holt’s a senior. Adding to the uncertainty is quarterback Zac Lee, who has only attempted two passes in his collegiate career.

The Associated Press poll came out Saturday, with Nebraska at No. 24 and Kansas at No. 25. With Castille’s dismissal, The Jayhawks are looking a lot better in the race for the Big 12 North crown.