Suspended cornerback Bradley Roby did what he could in preseason camp to coach and mentor the players taking his place in Ohio State’s first game.

But though the fourth-year junior All-American tried to pass on much of the knowledge he’s acquired, it could never be the same as having Roby himself manning the position.

After sitting out one game for an incident in an Indiana bar — a misdemeanor assault charge will be dismissed if he completes a diversion program — Roby will be back in action against San Diego State on Saturday.

The Buckeyes, who had a ho-hum 40-20 win over Buffalo in their opener, also will be fortified by the return of sophomore running back Rod Smith, who was suspended one game for an undisclosed off-field matter, and injured senior safety C.J. Barnett (ankle).

The return of Roby, who led the nation with 19 passes defended last season, and Barnett, a three-year starter, probably isn’t good news for San Diego State, which threw 63 times in a stunning 41-19 loss to an FCS opponent, Eastern Illinois.

Unlike Buffalo, which picked on inexperienced sophomore corner Armani Reeves, the Aztecs will have to look elsewhere for a soft spot in the OSU defense.

“Let’s hope they have 63 passes so we can go make a play on the ball,” senior safety Christian Bryant said.

“With our defense, especially our secondary, we feel like if they throw the ball down the field, we’ll make them pay.”

Roby certainly paid for his transgression under coach Urban Meyer’s zero-tolerance policy on legal matters. After getting skewered for numerous arrests under his watch at Florida, Meyer is handing out harsh discipline even if players end up not being charged.

But at his weekly press luncheon Monday, Meyer indicated Roby needed an attitude adjustment this summer after passing up a chance to leave early for the pros.

“He made a decision to come back, and I don’t know if he even announced why, but it’s because he came in with a group of players he wanted to finish with, which I think is very admirable,” Meyer said.

“He catches a lot of people in his ear, people that (say), ‘You could have done this, you could have done this.’ And then after you’ve been told that for so long, I believe he went through a little bit of a funk of buyer’s remorse.

“I’ve seen ever since the incident that occurred — which, once the (bar) videotape came out, there was no assault, there was no battery, there was no whatever — I think he learned a really strong lesson, and he’s done everything we’ve asked him to do. And I’m anxious to get him back on the field.”

Of course, a bolstered secondary won’t do much good for the offense, which sputtered after bolting to a 23-0 first-quarter lead against Buffalo.

The Buckeyes had 460 total yards — 210 in the first period, 250 in the final three.

“I have very high expectations. I want to score every time we touch the ball. I’m disappointed if we don’t score,” Meyer said.

“We have some talented guys. Our coaching staff has been together, and we should have been better. … I think we grade it very average for this game — without taking any disrespect on our opponent because they did a good job.”

The Buckeyes are still trying to work in veteran center Corey Linsley. He had offseason foot surgery and played fewer than 20 snaps against the Bulls.

“I have the utmost confidence in our offensive line and their position coach (Ed Warinner), what he did with them a year ago and what he is doing with them now,” Meyer said. “They will play much better, and they have to.”

Ouch: San Diego State, which shared the Mountain West Conference title last season with Boise State and Fresno State, committed five turnovers in becoming one of seven FBS teams last weekend to fall to schools from the division formerly known as I-AA.

The Aztacs, picked to finish second behind Fresno State in the West division this season, played most of the way without star running back Adam Muema (nearly a 1,500 rusher last year). He had one carry before suffering an ankle injury, and his status for the OSU game is uncertain.

Making debuts: Nine true freshmen played in the opener for the Buckeyes, including Trotwood’s Cam Burrows, who had a tackle on kickoff coverage

Middletown’s Jalin Marshall didn’t see action, although he still figures into OSU’s offensive plans. Another former Middie, defensive lineman Rashad Frazier, also didn’t get off the bench.