If that helmet coming off didn't clue you in, that was a big hit Braxton Miller took when he went up against San Diego. It was hard enough to knock the Heisman candidate out of the game in the first quarter.

Miller was taken off the field on a cart and was diagnosed with a left MCL injury, prompting Ohio State's medical staff to outfit the quarterback with a knee brace. The injury comes after Miller went 15-for-22 and two touchdowns last week against Buffalo.

The good news from the injury is that it gave Ken Guiton a chance to shine. He led the Buckeyes to back-to-back touchdowns to put the team up 14-0. So if Miller isn't 100 percent, Ohio State does have a man to fall back on.

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[via SB Nation]