Brennan Williams makes no attempts to hide his passions. A lover of anime, video games and all things Japanese, Williams regularly attends conventions across the country. His Twitter handle, @greatblackotaku, features the Japanese term for someone with obsessive interests.

Knee injuries brought a premature end to his NFL career, but they also opened the door for Williams to embark on a new career in a field he deeply loves: professional wrestling.

“I was going to be fighting the same uphill battle if I tried to come back to a training camp,” Williams said. “At some point I just figured I'm healthy, I've gotten a whole lot out of football, and it's time to move on to other things. I'm very fortunate to be a guy that has more than one passion. I can go onto a second dream after I went onto the first one.”

A native of Easton, Mass., Williams starred at Catholic Memorial before moving on to the University of North Carolina. A third-round draft pick of the Houston Texans in 2013, Williams suffered a microfracture in his knee that dogged him throughout his brief NFL career, which featured a stop in Jacksonville before ending with a one-day training camp appearance with his hometown New England Patriots this fall. Williams was brought in to fill a hole on the offensive line, but the team quickly decided to look to other players to fill the spot.

“I guess the cool thing is I got to finish where I started,” Williams said. “I'm from Boston, and even though I was with the Patriots for just a couple days it was the last time I put on a helmet. It's sort of a full circle thing.”

Williams' career in football was long. The oldest son of former Patriots defensive end Brent Williams, Brennan started playing Pop Warner football at the age of seven and worked his way up to being a star at CM. A U.S. Army All-American his senior year, Williams was a two-year starter at UNC and was named honorable mention All-ACC as a senior. He was drafted 89th overall by the Texans.

While with the Texans, he would regularly attend shows at the independent promotion Reality of Wrestling. Williams befriended the promoter for ROW, former six-time world champion and WWE Hall of Famer Booker Huffman Jr., widely known by his in-ring name Booker T. So when Williams decided to change careers, he knew where he wanted to go.

“When it came time that [I decided] I wanted to [wrestle] and take this seriously I had the opportunity, it was kind of an open offer, to come out for a WWE tryout,” Williams said. “I asked Booker because he still works for the company, and knows the business, and he recommended that I come learn the ropes from him and figure out what I want do so I can look as good as I can.” Williams was in training a week after his final NFL practice.

Former UNC star and Texans draft pick Brennan Williams, a high school All-American at Catholic Memorial, has always dreamed of wrestling in the WWE. Joel Auerbach/Getty Images

Football and wrestling are both incredibly grueling and physical, but are almost nothing alike. In football, offensive linemen aim to take their opponent out of the play, which often results in a violent collision. In wrestling, the goal is to make a show of hitting your opponent hard but, in reality, doing it as safely as possible for both wrestlers.

For Booker, training a football player provides unique opportunities, but also difficult challenges.

“Football players are actually the hardest to train as far as making the transition into wrestling just because they've been taught to hit, hit, hit as hard as they possibly could since they were a little kid,” Booker said. “I don't think the training is any more grueling than football training; it's just different. There's no other training that you can do, no working out, no cardio, to get you into wrestling shape. You've got to be out there and doing it.”

Williams was a fit 315 pounds as an NFL lineman but, by his own admission, got beaten up during his first few weeks of training. The intensity and pace of training conditioned him quickly to the speed of his new occupation. Now, roughly three months after starting training, Williams has lost 30 pounds.

“I compared it to when I was a kid and I would go from football season to basketball season,” Williams said. “I'd be in great shape for football, but as soon as it came to running around on a basketball court I felt like I was gonna die. I was in pretty good football shape, but it's just a whole other world conditioning wise.”

Athleticism is a necessity to thrive in wrestling, but the showmanship aspect is just as important. You can be able to do the most flips and suplexes in the world, but if you can't be a charismatic character there is a low ceiling for you. Williams took from his interests to create his ring persona. Taking from his love of anime and Japanese culture, Williams will step into the ring as Marcellus Black: Shogun of the ROW.

“When I was looking at different things as a character, what different do I bring to the table, it's you with the volume turned up to 11,” Williams said. “So the Shogun of the ROW is this big, bushido Wu-Tang Clan street samurai. I've never seen anyone run with that gimmick, and I think it has legs. We'll see.”

The end goal of nearly all wrestlers is performing for the WWE. No promotion has the reach or cultural might that the WWE has, and especially, for a young man like Williams, can potentially provide a steady enough income to raise a young family.

Williams' unique gimmick in Reality of Wrestling is heavily influenced by samurai folklore and the popular hip-hop group Wu-Tang Clan. Courtesy Reality Of Wrestling

Williams has a WWE tryout coming up in February at the company's performance and training center in Orlando. Having a handful of months to train for the event has Williams in the same state of mind that he had going into the NFL Combine coming out of college.

“The biggest thing is that I've got a wife and daughter so I've got to be able to sustain my family,” Williams said. “I'm not in any hurry to necessarily be on TV. I want to be good at this, and I'm taking it very seriously. I don't know how long that will take. I feel I've gotten pretty decent pretty fast so if I can keep that up maybe I'll be good pretty soon.”

Booker said that he was impressed with how Williams had taken to the business, from the in-ring training to setting up the ring and cleaning up after sessions. However, he did say he was worried that Williams might be biting off a bit more than he could chew with a tryout so soon.

“You want to be better than everyone else when they look at you,” Booker said. “You want them to say 'Wow.' If they say that, you win. If they say anything other than that you can really put yourself behind the eight ball. I think Brennan has all the tools, but I'd love to see him take a little bit more time before he went down there and did a tryout just because if they got 50 guys down there, and you don't perform better than 49 of them, you're not winning.”

Football players have always made for good wrestlers, a tradition that continues today with former college and pro players such as Roman Reigns and John Cena headlining events. P

Former NFL lineman Quinn Ojinnaka, who played in 62 games across seven seasons, is currently a rising star in the top independent promotion, Ring of Honor, performing as Moose. Williams said he'd work the grind across the independent circuit if it meant eventually reaching his goals within the wrestling business.

“I know there's a lot of different ways to go about it,” Williams said. “I've talked to Moose also about the same thing. I haven't really looked at how to break into the business from that standpoint. That's a real possibility because I do love this and I'd love to keep doing it no matter what. We'll see.”

For now though, Williams continues to train as he gets set for his big debut at the end of this month for ROW. Marcellus Black will step into the ring for the first time on Jan. 30 in Texas City, Texas.