A matchup with eighth-ranked Michigan State stands as Michigan's toughest test to date and will reveal whether the Wolverines are legitimate contenders. Madeline Hinkley/Daily. Buy this photo.

Fourteen years ago, Mike Hart stood behind a podium wearing a Block-M quarter-zip after beating Michigan State 28-24. He smirked; shrugged, then laughed. His “little brother” quote, now infamous, has become ingrained in the rhetoric of the rivalry.

This weekend, Hart will return to East Lansing as the running backs coach for the undefeated Wolverines. Michigan State also remains unbeaten, making this the first time since 1964 both teams play each other while ranked in the top 10. That year, No. 4 Michigan beat No. 9 Michigan State, 17-10. 

Now, the sixth-ranked Wolverines will play their toughest game of the season against the eighth-ranked Spartans. Throughout the year, those watching have speculated on how its performance against lesser opponents will golf up against more noteworthy opponents throughout the last five weeks of the regular season.

It’s the same story for the Spartans. Just like Michigan, neither have played against a team currently ranked in the top 25, and yet both are among the nine remaining undefeated teams, each with legitimate College Football Playoff hopes. 

Michigan State comes in with an explosive offense, led by running back Kenneth Walker III who tops the nation in rushing yards per game. It has three wide receivers — Jalen Nailor, Tre Mosley and Jayden Reed — who average over 15 yards a catch, each with more than 20 catches on the season.

For reference, the Wolverines don’t have a single player with more than 20 catches this season. It does, however, have two top-50 running backs in rushing yards per game. And, as a unit, the running backs room out rushed the Spartans by more than 300 yards this season. 

But the Spartans’ weapons strike at a weakness of the Michigan defense that first revealed its flaw three weeks ago against Nebraska. The Cornhuskers totaled eight plays of 20-plus yards against Michigan, consisting of more than half their yards over the game. Northwestern’s one touchdown, meanwhile, came on a 75-yard touchdown run. 

Michigan State has 38 plays of 20-plus yards on the season and nine plays of 50-plus yards, good for fifth in the nation. 

And then there’s Michigan’s offense, much-maligned amongst the fanbase. No, freshman J.J. McCarthy will not be the quarterback, for better or worse. Junior Cade McNamara will game-manage an offense that is led by running backs Blake Corum and Hassan Haskins and if the defense limits big plays, the game will be decided by one of those two running backs. 

At least, that’s what we think. The past two months have merely been a rehearsal for Saturday and November, with Washington and Wisconsin not being the measuring sticks we expected. A game against top-10 Michigan State may go along the script we expect, or it may not. McNamara could make plays and blow the game wide open, or he may be taken aback by the most hostile environment he has ever played in.

Either way, the game will act as an all-important barometer going forward. It’s a test that will measure the capability of the entire team and the coach at the helm.

Jim Harbaugh, whose proverbeal seat has considerably cooled in this season’s first seven weeks, will coach in a pivotal game against a rival. Can he dispell the narrative of struggling against rivals and struggling in big away games? Or by 4 pm on Saturday, will one more game be added as an indictment against him?

“All focus is there,” Harbaugh said after the Northwestern game. “When you walk through that door I am going to answer some questions about this game, but it’s on to that game right now.”

Throughout the last eight weeks of Michigan’s schedule, more questions have been asked than opportunities to answer them. The team has an identity, a solid foundation. 

On Saturday, we will know if that foundation is strong enough to support a potential playoff push. 

Or if the “little brother” can knock it over like a sand castle.

Managing Sports Editor Kent Schwartz can be reached on Twitter at @nottherealkent