Found: Paul Bunyan

In 2010. Less happier times.
There was a bit of confusion last night when the clock struck zeros and some of the Michigan football players went straight to the MSU sideline, looking for the Paul Bunyan Trophy. Little did they know, Paul wasn't there.
After beating the Wolverines for a fourth straight time last season, Michigan State players were seen celebrating with the massive trophy on the field at Spartan Stadium. On Saturday, though, the exchange was more low-key -- it was done somewhere inside the stadium tunnel, and the trophy was waiting for the Wolverines in their locker room after the game.

A Michigan spokesman said that it's generally been common practice, for Michigan at least, to not bring the trophy onto the field after the game. In large part, because, it's so massive.

Michigan said the trophy was, to its knowledge, never on the sidelines Saturday -- and was likely exchanged between equipment managers after the contest.
Video evidence:

As far as I can remember, I don't recall Michigan players ever celebrating with the trophy on the field after a win. However, I can recall vividly Spartan players doing victory laps around the field the last two years. I guess some find Paul a little more appealing than others.

Welcome home Paul.