When he does eventually return to the field, though, he'll have more than a new playbook to worry about.
"Obviously there's some uncertainty with Johnny right now and that's why we brought in Josh (McCown)," Thomas said. "He's a guy that if he's asked to carry the flag this year, he's going to do a great job. There's a chance we draft somebody or there's a chance Johnny comes back and he's a new person and he's rededicated to football, and he turns into the great quarterback that we expected when we drafted him in the first round."
Thomas added: "You know, I think he lost probably a lot of trust among the guys on the team last year by the way he handled himself once he became the starter. And I think he had a lot of time to reflect, I'm guessing, after the season was over by the comments he made in the media and by his actions, checking himself into rehab. ... I think those were really positive steps."
First off, there's nothing more important for Manziel than taking care of his mental and physical health, and Thomas is right, checking himself in was far and away the most crucial part of the process.
But he does raise an interesting question about how dependable Manziel will seem to his teammates once he returns. Various reports have suggested the team is fully prepared to move on from the immensely talented college quarterback.
Could he earn himself a second chance?