During his weekly radio show on Thursday night, Purdue first-year coach Ryan Walters did not hold back.

Two days before his Boilermakers travel to Michigan Stadium to meet No. 2 Michigan, he spoke as publicly candid as any administrator or coach about the Wolverines’ alleged sign-stealing scheme.

“It's unfortunate. What's crazy is they weren't allegations,” he said. “It happened. There's video evidence. There's ticket purchases and sales that you can track back. We know for a fact that they were at a number of our games, so we've had to teach our guys a new language in terms of some signals.”

Purdue has the receipts.