Mahomes' father was a big league pitcher for 11 years. Dieter's father was a baseball nut to the point where he named his three sons after former Major League players Thurman Munson, Nolan Ryan and Lou Gehrig.
Maybe it was baseball. Maybe it was because they share a similar Sideshow Bob style of haircut. Maybe it was the fact that Mahomes, the prized first-round pick, had a car when the two arrived in Kansas City and Dieter didn't. The rookie receiver began riding shotgun to the facility on a daily basis. The two became BFFs pretty much instantly.
"We're just boys, man," Dieter told me recently in a back office at the Chiefs facility after their second day of minicamp. "We get along really well. We have personalities that match each other's. We're both hard on each other. We both mess with each other with every single thing we do. The biggest thing, though, is we're both super competitive. That brings a different side of us into each other."
But it isn't just football-related activities where Mahomes and Dieter spend their time together. Dieter's fiance and Mahomes' girlfriend are close, and the four of them go out to eat regularly. The teammates play golf and it's a toss-up to who is the better player in "NBA 2K16" or "Fortnite."
A week after their rookie season was over, Mahomes and Dieter were in the weight room at the Chiefs facility every day for roughly a month and a half. Mahomes went back home for about a month and with the Chiefstrading Alex Smith to the Redskins in January, returned to Kansas City as the starter. Dieter decided to stay and train alongside him.
"He's the man now," Dieter said comparing this offseason to last year's. "I think he knows that and I think he's ready for that challenge to step up to the plate and take this team to another championship. That's all you want in a quarterback is a guy that will lead you to the Promised Land."
Who better to know if Mahomes is ready to lead this team to its first Super Bowl since 1969 than his best friend? Dieter does compete alongside him every day on the football field and against him on the golf course or video games.
"He's just super competitive," Dieter said about Mahomes. "Alex (Smith) was super competitive, too. To play football you just have to be a super competitive guy. The quarterback, I think, has to be one of the most competitive guys on the team. And I think he is. I think that's the biggest trait in a player is being competitive. If something is going wrong and we're losing, you don't want a guy that is going to quit and give up. He's always fighting and never giving up."
Mahomes has put in the work, too. They continued to work out together. Mahomes didn't bulk up, but instead transformed his body. Changed his diet and lowered his body fat. The two threw together weekly, with almost every receiver on the team popping in on the sessions from time to time when they were in town. Usually the workout would last for around 45 minutes and most of time it was rather laid back. With it now being his team to lead, it's that bonding time between Mahomes and his receivers that in the long run could perhaps be the most important part of the workouts.
"The more time you spend together the better the relationships you build," Dieter said of Mahomes. "You can see some of the relationships he has with some of the guys on team. I think that shows when we're at practice and he trusts them to do what their job is."
Mahomes' footwork has improved tremendously in the eyes of the coaching staff, and they believe he's a natural leader. He's been taking guys behind the scenes and working with them individually. And if there is a mistake made during practice, it's Mahomes who wants to be the one that takes over and fixes the issue himself.
"He's running it pretty close to textbook of how the playbook says to run it," wide receiver Chris Conley told me. "But he's got his little flavor on it. But also at the same time he's asking us questions while we're doing things. He knows how he wants routes run, but then it's not to the point where he won't ask your opinion and what your thoughts are. It's kind of easy for you to go up to him too and say, 'I know this is what you're trying to get done, but this is what we're seeing.'
"So there is a lot of open dialogue right now between us and him, but also at the same time, I don't think he's afraid enough to say, 'This is how I want it,' which is good. Sometimes young guys will be passive, but he's not at all."