You know it's a rivalry game when...

Michigan head coach Jim Harbaugh has become somewhat renown this season for not releasing a weekly depth chart for the Wolverines, ostensibly in an effort to give his team a competitive edge.

His counterpart at Michigan State, Mark Dantonio, however, has always released a weekly depth chart throughout his seasons in East Lansing.

Until now.

In their weekly game notes, Michigan State withheld its depth chart for the rivalry game with U-M. This, obviously, is out of the ordinary: MSU usually puts its depth chart in these packets, as you can see in past editions. (Sidebar: No one among the media contingent at Dantonio's weekly press conference on Tuesday could recall the Spartans withholding their depth chart in recent memory.)

So there you have it. Rivalry week is officially under way with our first cat-and-mouse game between the two head coaches. Next, maybe Dantonio and Harbaugh will play coy with the media about potential alternate uniforms they'll wear on Saturday?