ST. JOSEPH, Mo. (TNS) — Sometimes, Eric Berry's mind wanders to the what-ifs.

What if he didn't have two season-ending injuries?

What if he never got cancer?

What if he didn't spend nearly half of his NFL career on the mend?

But before the five-time Pro Bowl safety can escape too far down the rabbit hole of alternate realities, he pauses and remembers the positives that came from those negatives.

"You really can't wonder where you would be," Berry said. "There's no telling. Because I learned so much throughout all three of those processes _ including this one _ and I just keep growing. I can't really tell you where I would be without them."

Saturday morning, Berry pulled on pads for the first time since he exited the season-opener against New England with a torn Achilles in the fourth quarter.

Right before he went down, Berry felt like he was finally close to peaking. He was in excellent shape and primed for a big season. He had the same feelings in 2011 and 2014 when his seasons were cut short by an ACL tear and a Hodgkin lymphoma diagnosis, respectively.

It would be easy to feel cheated by the cruel timing of those maladies, but Berry doesn't.

"I learned so much," he said. "The whole cancer deal was actually a privilege, to be honest with you. It was a blessing at the same time because I learned so much. I helped so many people and so many people helped me as well and inspired me, just being able to connect with them through that common thread of having cancer and being able to overcome it."

His experience recovering from the ACL tear and the cancer fueled him through his latest rehabilitation, and he tried to follow the same blueprint he used then to get ready for this season.

But at nearly 30 years old, Berry knows his body can't take the physical beating the way it used to. So much of his preparation now is mental. He relies on putting in work in the film room and in walk-throughs instead of banging bodies during extended 11-on-11 scenarios.

"You can't overdo it physically," he said. "You've got to make sure you prepare mentally because you only get a few opportunities on the field to be like, 'OK, this is the situation, this is the down and distance. Let's see if we can make the play or make sure we are perfect on this play, make sure we get it done.' Because you only going to get so many reps on the field where you get a game-like situation."

After three catastrophic setbacks, it would be easy to get discouraged.

But Berry's support network doesn't let that happen. Before Berry departed for training camp, his dad gave him the same advice he's given him during each of his rehabilitation journeys.

"Sometimes I might tend to overthink things at times instead of just doing it," Berry said. "He's always been the person to ground me and keep me humble, and also put things in perspective for me. ... He's always been there to be like, 'Look, just take care of business. And you'll be fine.' "

Berry's journey isn't lost on his teammates. Entering his ninth year with the organization, Berry is the unquestioned leader of the young group, and his status as the comeback king only builds his legacy in the locker room.

"Eric's our leader," Chiefs coach Andy Reid said. "We appreciate when he's out there going. The guys feed off him. It's the whole story. It's not just that it's Eric Berry, It's the whole story, the whole thing that he went through. The fact that he does everything out here and works his tail off. It's a phenomenal story."

Berry doesn't know what this season will bring. He doesn't know if he has another comeback in his system. But he's not worried about what he can't control.

"I just keep on trucking," Berry said. "I don't know what life is going to throw at me. That's just period. You never know what's going to come your way. However it comes to you or whatever it is, you just roll with the punches and keep pressing forward."