The criticism is that Shanahan shouldn’t have left Griffin in the playoff game against the Seahawks in the 2012 season. The rookie quarterback came into the game gimpy with a strained LCL and left the field after taking some hard hits early. He came back out, and his knee buckled in the fourth quarter.

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RGIII suffered a partially torn LCL and ACL as a result, and people wondered if he’d ever again be able to showcase the special talent he displayed as a rookie. After undergoing offseason surgery on his knee, Griffin sat out the preseason and started Week 1 of the 2013 season.

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How different would his career have been if he didn’t suffer that gruesome injury at the end of his rookie year? Shanahan believes it wouldn’t have made a difference.

“I don’t think the injury had anything to do with it,” he told MMQB. “When we started 2013, in the preseason, Dr. [James] Andrews gave him 100 percent full go. He told me at the start of training camp that there was no need to hold him back.”

However, Shanahan was a bit cautious with RGIII and didn’t want him to take too many hits early. So Shanahan took away some of the read-option plays in the first few weeks of the season, but that “wasn’t natural” for Griffin, according to the coach.

“What wasn’t natural, like in the first three games, was for him to sit back and drop and throw,” he said. “It had nothing to do with the injury. It had to [do] with his background in a drop-back attack. The rest is kind of documented what happened after that, that he really believed that he wanted to throw the ball more and run less, and that wasn’t going to work with me running the offense.

“That’s one of the reasons Jay (Gruden) was hired: He was going to run a drop-back attack, and Jay has done that. Robert wasn’t completely comfortable in that, and I think that has proven out over the last couple years.”

What Shanahan is essentially saying is that RGIII isn’t going to perform well in a strictly drop-back style offense. He needs to utilize his legs and be in a system that will allow him to do that. He believes Griffin has that in Cleveland with Hue Jackson, and that he’ll be able to get back to his 2012 self.

But he does offer caution to his former QB, saying he has to give it his all.

“Robert is going to have to be all-in, and he should be right now, given the fact that his options are limited,” Shanahan said. “Hue will make that decision, and Robert has to buy in. If he doesn’t buy in, then Robert will be out of the league.”