The Ohio State Buckeyes have proved time and time again that they can make appropriate changes when needed. When Miller was injured, the Buckeyes proved they had a competent backup quarterback, J.T Barrett, who actually has better statistics than Miller when it comes to the passing game. Barrett was a bit unsteady in the start of the season, such as the punishing Virginia Tech. Loss, but since then he has greatly improved, and can easily be seen as leading the team to the National Championship. Proof of this was when Barrett faced up against and pounded Michigan State, who was ranked with one of the best Defenses in the country.
As the starting QB for the past three seasons, Braxton Miller is the core of the Buckeye's offense. With the season opener a few weeks away, there is not enough time to train a back up quarterback. Simply put, without Miller, the Buckeye's season is over before the first game.
As if losing a Heisman Trophy candidate for the season wasn't bad enough, the Buckeyes are also returning only one starter on their offensive line, and their backup quarterback is a freshman. For a freshman quarterback to come in, under those conditions, and elevate a team into national title contention is virtually impossible.
I do not believe the Ohio Buckeyes will make it to the national title, but I think it's unlikely for them even with Braxton Miller. With the re-injury it's clear that he will only be there with half gusto he would have had without the injury. I think it's something they'll be watching all season.
Not only was he an amazing quarterback, he was also a senior and a leader on their team. Their backups are not ready for the role and so this would be a huge set back for the team. I doubt they would even make it to a bowl game if he was out.