There have been a few bumps along the way and the biggest game on the regular-season schedule for both teams has lost some of its luster from when it looked like a potential 1-2 matchup in September.
But it is still a really big deal.
The loser cedes control of the Big Ten East title. Without that, there is no Big Ten championship, and without that, you might as well say goodbye to the College Football Playoff.
''All the goals are right in front of us,'' Michigan State coach Mark Dantonio said.
The first 10 games of the season for the Buckeyes (10-0, 6-0) seemed like preliminaries. Playing nothing but unranked teams, they haven't been nearly as dominant as expected for the first unanimous preseason No. 1 in the history of The Associated Press poll.
Still, they arrive at the make-or-break part of the season as expected and in position to repeat. With one good performance against the Spartans, all the angst about the Buckeyes goes away.
Of course, if Ohio State does not take care of business in the Horseshoe, then all the skeptics can claim that the Buckeyes have, indeed, been fraudulent all along.
''I think people are still unsure of what we got,'' running back Ezekiel Elliott said. ''It's a game to go out there and show who we are and what we can do.''
Michigan State (9-1, 5-1) lives in a perpetual state of proving its worthy of elite status. They are 13-point underdogs to Ohio State.
''We're used to it around here,'' center Jack Allen said. ''Every big game we're in, we're always expected to lose, and feel like surprise a lot of people and make a lot of people look foolish.''
But if Michigan State can beat Ohio State for the second time in three years and end another 20-plus-game winning streak for Urban Meyer's Buckeyes, the blemishes will be hardly noticeable.
''I think we have talent to play with the top-10 teams in the country, I do,'' said Dantonio, whose team is 5-1 in its last six games against top-10 teams. ''I don't think we have yet to put our best game in front of us, play our best game, where we're hitting on all cylinders.''
Michigan State quarterback Connor Cook missed much of last week's game after taking a shot to his throwing shoulder.
He says he is fine and Dantonio has said Cook is a 9 1/2 out of 10. Cook is an Ohio native who wasn't recruited by the Buckeyes, and the Spartans can't afford for him to be less than excellent on Saturday. Cook has passed for 2,482 yards, 21 touchdowns and four interceptions.
''What you want in a quarterback, you pretty much see in him,'' Ohio State co-defensive coordinator Chris Ash said.
Elliott has 15 straight games of at least 100 yards rushing, not including the 154 and two touchdowns in the 49-37 victory at Michigan State last year.
The Buckeyes have been one of the few teams to effectively run against Michigan State each of the last two years, when the Spartans had the top rush defense in the Big Ten and one of the best in the nation.
Even in Michigan State's 34-24 upset of the Buckeyes in the 2013 Big Ten championship game, Ohio State ran for 273 yards. That is the only game the Buckeyes have lost to a Big Ten opponent since Meyer became coach in 2012.
IN THE TRENCHES
Michigan State's defensive line, led by defensive end Shilique Calhoun, is among the best in the nation and has helped the Spartans rack up 29 sacks, tied for 14th best in the country.
The Buckeyes have given up sacks in a little over 5 percent of their pass attempts, which ranks 45th in the country.
Ohio State has won 23 games in a row, the longest streak in the nation, and 30 straight Big Ten regular-season games. The Buckeyes had won 24 straight when they lost to Michigan State in the conference title game two seasons ago.
The last three times an unbeaten Ohio State team played a late-season game (November or later) against Michigan State the Spartans have won (1974, 1998 and 2013).
AP College Football site: http://collegefootball.ap.org/
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