If you want to find Gotham boxing coach and United States Marine Sgt., Mike Castle, check the gym. Whether it’s five a.m. or five hours shy of tomorrow’s five a.m., he’s there for you. He may be barking at you for one more rep—the one that separates winners from their counterparts—or doing mitt-work with two fighters at a time, without ever missing a beat of the Rocky theme-song playing in the background. Or he may be getting punched in the face with a smile, sparring with you just hard enough to keep you honest, and just easy enough to give you confidence in the days leading up to your next fight. Whatever he’s doing, Mike’s there for you.

Mike’s loyalty may have been what first drew him to the sport as a child. Boxing was important to the people around him, so it became important to Mike. He was the oldest of five brothers, all two or three years apart, so he felt like he was always fighting from the very start. Both his grandfather and his father were boxers, so there may have been a certain inevitability to it. Mike describes his first experience at a boxing gym in Washington Heights:

“I got knocked out the first time I put on a pair of gloves, by my cousin, who was three years older than me and literally half my weight. He knocked me out with a body shot.” I should interject, Mike was a big boy when he was young: with 315 pounds of body weight surrounding him, getting knocked out by a body shot was no small feat. “I woke up on the floor,” he says, “But I came back the next day and fought again.” Years later, Mike’s first trainer told him, “I knew you were a boxer forever, ‘cause most people who get knocked out the first day don’t come back.”

Big Mike was hooked. Never one to give up on anything or anyone, boxing became a way for him to give back. It gave so much to his health—helping him to lose over a hundred pounds—and inspired those around him. When people saw the physical transformation and startling weight loss, they started asking Mike to train them. By the age of 15, he was training the other neighborhood kids (and adults!) out of a small gym in Washington Heights. He stood behind his fighters, even back then. “Even though you’re training people, you learn so much about life from the people that you’re training,” Mike explains. There’s a certain dialectic to coaching for him. Mike tells his fighters, “You won’t believe me, but you’re training me more than I’m training you.” For him, that process of mutual learning, of collaboration, is the most meaningful part of training his fighters: “Watching a fighter apply what we’ve learned together, practicing together, fighting together, winning. Together.”

Cohesion and teamwork are certainly some of Mike’s finer traits, but let’s not forget about his competitive side. The “first” time I met Mike was right before my own Haymakers fight at the PlayStation Theater (formerly Best Buy Theater) in New York. I was already as nervous as could be; maybe that kind of nervous you can only really be before your first fight, especially in front of a crowd that size. A friend and fellow coach from my gym introduced me to Mike, who was all-smiles and all-jokes with hoards of friends and fighters from the boxing world gathered around him. He gave me one of his signature Big Mike grins, shook my hand, and said it was a pleasure to meet. I told him that we had sort of met once before, at the Haymakers sparring day, where fighters have a chance to spar with their prospective opponents in preparation for the big event. I then told him I would be fighting Joe, who happened to be one of his guys.

Mike instantly went from all-smiles to all-business. He looked me straight in the eye and said, “Oh, I’m so sorry man. I’m so sorry for your loved ones that won’t have you around tomorrow, cause Joe is gonna murder you tonight.” I gave him a nervous laugh, shook his hand again (this time with a little less gusto) and went to find a place that may be acceptable to throw up just in case the fear he’d shoved down my throat were to creep back up. Now that I’m close with Mike, we joke about it, but what I’ve never told him is that he really kinda scared the hell out of me that night. And that’s what a great coach does, I think. He fights for his boxers as much as they fight for him. He stands for his people, as I found out, to the (frighteningly) bitter end.

After his fighters’ recorded a perfect 8-0 in the recent Haymakers NYC event this past November, there’s a certain renewed faith in Mike’s fighter philosophy and loyalty to the sport. It was probably that same faith that drew Mike to join the Marines at the age of 18, or maybe the Marine’s actually drew it out of him. But either way, Big Mike is Semper Fidelis to the very end. With all of his fighters, he is always faithful, always there. He is one of the most loyal boxing coaches in the game, and the Haymakers For Hope team is certainly lucky to have him in our corner.

P.S. Since this article was originally written, Haymakers has learned that Big Mike and his wife, Angelin, are expecting their first child! Be sure to reach out and congratulate him on the new addition to the family!