Patrick Maks notes, “head coaches Urban Meyer and Mark Dantonio have been quick to dismiss this as a rivalry game...even if it feels that way.”

Does it not feel that way? How and when does a rival, become a rival?

I am not aware of any - official - rivalry inaugurations having ever been convened - much less proclaimed - in college football history. But, now that Sparty has become an every-year reality on the Buckeyes’ schedule (by 2013 B1G mandate) it makes their series (Ohio State leads MSU, 28-14, all-time) and its history, worthy of consideration in this regard. As Bill Connelly writes: 

Michigan State has been pretty good at wrecking Ohio State's plans through the years.

In Duffy Daugherty's final season as the Spartans' coach, a 3-4-1 MSU team took down 1972's undefeated Ohio State, 19-12, in East Lansing. Two years later, Dennis Stolz's 4-3-1 team beat the undefeated, top-ranked Buckeyes, 16-13, with a finish former players still debate 40 years later. It was the Buckeyes' only regular season loss in each year.

In 1998, young Nick Saban took his 4-4 Michigan State squad to the Horseshoe to face John Cooper's dominant, top-ranked Buckeyes. The Spartans left town with a stunning, 28-24 win, one that kept Ohio State out of the BCS' first title game.

Last December, the two schools met in the Big Ten Championship in Indianapolis. No. 10 Michigan State knocked out undefeated No. 2 Ohio State, 34-24, denying the Buckeyes another BCS title game bid.

http://www.sbnation.com/college-football/2014/11/6/7166749/ohio-state-mi...

After all, don’t we sing, “We don’t give a damn for the whole state of Michigan!”(?):

Ohio State claims seven national titles. If not for Michigan State, the Buckeyes might claim 11. As deep as college football's history runs, certain conference rivalries create specific roles. Michigan State is Ohio State's spoiler. The Spartans are pretty good at that role.

http://www.sbnation.com/college-football/2014/11/6/7166749/ohio-state-mi...