"It wasn't a mistake of judgment, it was a mistake of an application of the rule," Delany said.
Delany said discipline could follow.
Michigan's Brandon Minor leaped to make a catch and knocked over the pylon at the front corner of the end zone on his way down, causing the on-field referee to rule the play incomplete.
The replay official overturned the call, ruling that because Minor's foot hit the pylon, it was a touchdown. According to NCAA rules, however, an airborne player who touches a pylon is considered out of bounds.