Perfect through the first four games of the season, the Ohio State Buckeyes will face their biggest test thus far in 2012 on Saturday when they take on the Michigan State Spartans at Spartan Stadium.

Urban Meyer's team struggled at times against UAB last weekend despite pulling out a 29-15 win, but will not be afforded the same luxury against a Michigan State defensive unit that ranks among the best in America. The Spartans also enter after a somewhat lackluster effort in a 23-7 victory over Eastern Michigan, and will be desperate to avoid losing their second game in three weeks.

Buckeyes quarterback Braxton Miller remains the unquestioned key to the offense as the team's leading passer and rusher at the moment, and will be looking to bounce back against the Spartans after struggling as a freshman in last year's meeting. Miller has already racked up 14 touchdowns (seven passing, seven rushing) through just four games, but will need to be careful against a defense that excels against undersized running quarterbacks.

When: Saturday, Sept. 29

Game time: 3:30 p.m. ET

TV channel: ABC

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