"I just give it my best, and whatever happens happens," Heinicke said. "You just go out there, you try to do your best – do what you can do on the field, in the meeting rooms, in the weight rooms – and that's all you can do, really."

That simple formula has served Heinicke well. Since going undrafted out of Old Dominion in 2015, Heinicke has managed to be on a 53-man roster leading up to the opener in each of his four NFL seasons (he did start the 2016 season on the Vikings non-football injury list but was activated once eligible).

But this, with the late-season emergence of Allen and the investment of an early draft pick in Grier, could be Heinicke's greatest challenge yet.

"I think it's going to be a really good battle," Allen said. "Me, Taylor and Will all out here battling it out. And the good thing about it is that we're three good dudes. There's not going to be animosity or anything like that in the quarterback room. There's a lot of talent in that room, and I think we're all going to make each other better."

Heinicke agrees, but he's also been working on his own to make himself better.

After undergoing surgery just after New Year's Day, Heinicke spent most of the winter in his native Atlanta. He replayed the Falcons game in his mind, learning from the experience how hard it can be to succeed in the red zone on the pro level and learning from his injury that he needed to bulk up (He and Grier both stand 6-foot-1 but Grier weighs 10 pounds more at 220; Allen is two inches taller).

For a while though, Heinicke was limited to replays of some of his favorite shows, watching "The Office" and "Breaking Bad" over again and continuing his tradition of watching the entire series to date leading up to a new season of "Game of Thrones."

Eventually he was able to start getting back into football mode.

"I started losing my mind a little bit there, so I'd go to the gym and do footwork drills," Heinicke said. "Then towards the end with the brace, I did do some throwing which actually helped me a little bit because without being able to use my left arm I was forced to use my hips more. That helped me throw a little better."

Heinicke knows he'll have to be a little better across the board to emerge from Carolina's quarterback competition. Along the way, he suspects all of Carolina's quarterbacks will get better.

"If I'm in there and they see something I don't, they come up and tell me," Heinicke said. "We're all helping each other get better. That's all you can really ask for.