HOUSTON — Joey Mbu didn’t even know Trent Williams co-owned a gym 40 minutes from his home here until this offseason, but it’s been a boon to the Redskins defensive lineman as he enters his third season with an opportunity to crack the 53-man roster. Mbu started working out at O Athletik in February when he received an invite from Williams at the end of the season, and returned to the facility after the Redskins wrapped up minicamp last month.

Although Mbu didn’t know specifically how much muscle he’s gained and fat he’s lost, he’s around 320 pounds with training camp less than a week away. The results have been noticeable in his arms and shoulders after working out with Williams, running backs Adrian Peterson, Melvin Gordon and Ty Montgomery, and defensive linemen Jerry Hughes, Danielle Hunter and Tom Johnson.

“I’m not gonna front,” Mbu said. “At first, I was shellshocked. You see Adrian Peterson, you know he’s a legend. You see Trent, you know he’s a legend. Then you got people coming out here [and] hopping on like Melvin Gordon and Ty, people that I came in with in the draft and seeing them be successful. It’s like you work out with greatness, you become greatness. That’s how I take it.”

The workouts have been an “eye opener” for Mbu, who will take part in the team’s biggest position battle in Richmond this summer. Washington revamped its defensive line this offseason with the additions of free agents Terrell McClain and Stacy McGee, first-round draft pick Jonathan Allen and defensive line coach Jim Tomsula. Mbu, who went undrafted out of Houston in 2015, signed a futures contract following half of a season on the Redskins’ practice squad. He’s played only two NFL games in his career during his rookie season with the Atlanta Falcons, who cut him from their practice squad before the 2016 season.

“I’ve been working out with people who have made their mark in the NFL, and I’m just trying to make mine, too,” Mbu said. “I’m learning the ins-and-outs of football from them and just trying to soak up anything I can for this next season.”

Tomsula rewarded Mbu for the work he put in this offseason by giving him first-team reps throughout offseason practices and minicamp, but he’s eager to show his growth when the team can finally put on pads next week.

“OTAs is a trial thing,” Mbu said. “You don’t read — well, I don’t read too much into it. Certainly, some coaches don’t read too much into it. Getting the opportunity to give some type of impression was big for me, and I didn’t look back. I tried to focus on what I had to do, tried to learn some other things as well. I picked up a lot. I learned a lot of football knowledge in OTAs this year.”

His offseason outside of football has been — well, football. If he’s not in the gym, Mbu said he’s either eating, watching film or retweeting jokes on Twitter (@NotoriousMbu). He has limited the amount of his precious fruit snacks and gummy bears he eats while on a daily intake of 4,500-5,000 calories.

“It’s not hard when you have a bigger goal,” Mbu said. “If it’s just that I’m trying to cut it out just to cut it out, that’s when it’s harder. But I have a bigger goal in mind, and I’m trying to make an impact with the Redskins. That’s my goal.”