Ryan Day knows Justin Fields’ potential.

“Off the charts,” the Ohio State coach said of his starting quarterback on his radio show Thursday.

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Fields is intelligent and has all of the physical skills, both as a passer and runner, Day said.

But the coach cautions that Fields’ inexperience will also be apparent Saturday when the Georgia transfer makes his collegiate starting debut against Florida Atlantic.

The truth is, Day said last week, he doesn’t really know what to expect right away from Fields. In December, Tate Martell said he was confident that he would win a quarterback competition with Fields because it takes extensive time to master Day’s offense.

Martell instead transferred to the University of Miami, but his point remains valid. How close is Fields to knowing the offense well enough to be successful?

“I don't know the answer to that,” Day said. “I'll have a better idea here in a few weeks.”

He said the sophomore has to be able to transfer his knowledge from the meeting room into the game.

“I think sometimes you know something on the board,” Day said, “but to say you actually know it, you'll know when you get on the field in front of 110,000.”

On his radio show, Day compared the terminology a new quarterback must master to learning Chinese. Ohio State and Georgia might run the same play, but the play call for it might be completely different. Mastering that requires practice rep after practice rep. Then there are the reads before the play to make sure the offense is aligned properly, and the instantaneous reactions once the play begins.

“There's a lot that goes into being a quarterback, especially at Ohio State,” Day said. “We throw a lot of football at our quarterbacks, whether it's in the run game or pass game. We expect them to make a lot of pre-snap decisions and post-snap (decisions).”

Day waited until midway through training camp to name Fields the starter, though there was little doubt he’d get the nod. Early in camp, Day said, Fields too often threw into traffic.

But Day said he wasn’t disappointed in Fields’ play. He expected mistakes.

“How many guys are ready to be the starter after 17, 18, 19 practices?” Day said.

He said coaches would scale back the playbook in the weekly game plan to ease Fields in. As he becomes more comfortable with the offense, plays will be added.

“He's still not a finished product by any stretch of the imagination,” Day said a week ago. “He's just in the beginning stages, but I thought he took care of the ball last week better. He moved the offense better and had a great approach.”

The Buckeyes have to be careful how they use Fields. His legs are expected to be a major weapon, but with backups Gunnar Hoak and Chris Chugunov having little experience, as well, it would be foolish to expose Fields to more injury risk than necessary.

The Buckeyes will likely try to ride the running of J.K. Dobbins to ease the pressure on Fields.

“He's got it all,” Day said of Fields’ skill set. “He just doesn’t have experience, so the guys around him have got to help early. He's got to not have a lot of expectations of what the first game is going to bring. Just keep learning, knowing it’s a journey. And we’ve just got to end up 1-0 on Saturday.”

brabinowitz@dispatch.com

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