A noticeably slimmer Ian Mahinmi at Wizards media day on Monday. (Nick Wass/AP)

Last season, Washington Wizards center Ian Mahinmi had to sit and watch 51 games. He was sidelined by soreness in his right knee, then later betrayed by his left knee. The injuries resulted in a false start for his first season in Washington, but as Mahinmi recovered from his courtside seat on the Wizards bench, he observed and studied. Mahinmi noticed how quick his teammates played — and how their style matched the rapidly evolving league. These lessons would define his summer and reshape his mind and body.

“With everything that happened to my knee last year,” Mahinmi said. “I felt like I needed a change.”

In preparation for his 11th NBA season, Mahinmi, who underwent a minor knee procedure in the offseason, came into training camp as a leaner version of the 262-pound big man who signed with the Wizards last summer. Although Mahinmi doesn’t want to share the total weight loss — his lifestyle change in dieting is ongoing — he does appear to be less bulky. The slighter frame is for the purpose of matching up with the likes of floor-spacing centers and tracking, as best as he can, pick-and-rolling point guards.

“Since I watched so much, I watched the game from the sidelines, I realized,” Mahinmi said, explaining his decision last season to transform his body. “Here, we [put the] pedal to the floor. We’re [in] attack mode every day. Every game. Last year I realized — first of all, I like to play like that — I realized this is what’s working for this league now.”

Said Coach Scott Brooks: “It’s about being nimble on your feet and showing athleticism because you’re guarding a lot of pick and rolls up top. A lot of guards are coming at you downhill, so you have to be able to move your feet. He’s not as muscular, but he’s in great shape. This year he’s lost some weight and I think it’s going to help him long term.”

Although small-ball proved to be more than just a fad when the Golden State Warriors started their run of dominance in 2015, the degree of change stuns Mahinmi.

Only two seasons ago, Mahinmi was packing on the pounds to play a more significant role for his former team, the Indiana Pacers. During the Pacers’ 2015 training camp, a popular story line centered on Mahinmi’s muscles as he prepared to start at center for the first time in his career. The Pacers played half-court basketball. The slower, the better. And Mahinmi’s main objective was to protect the paint.

At that time, Mahinmi was replacing 7-2 center Roy Hibbert, who was not far removed from his peak as a 2014 Eastern Conference all-star. Hibbert was also once the muse behind the leaguewide defensive revolution of jumping straight up to block shots. Just two years later, Mahinmi no longer eats bread while Hibbert is working out in Los Angeles, waiting for an NBA team to offer him a contract.

“It’s crazy,” Mahinmi said, expressing disbelief at how rapidly the game has changed. “I put on some pounds [in 2015] because at that time we still had conventional bigs that post you up and you had to do a good amount of banging. This time, this season and the way we play, it’s the opposite. You’re not going that much on the blocks. You have to keep up with John [Wall]. There’s a whole lot more running.”

Mahinmi shared a similar realization that hit 7-foot teammate Jason Smith. Last season, Smith memorably said, “evolve or die” and forced himself to become a three-point shooter. Another frontcourt teammate, 33-year-old Marcin Gortat, has seen the change too but seems relieved to be in the twilight of his career, rather than morphing into a stretch-five.

“I’m not going to shoot threes,” Gortat said at the team’s media day. “I’m not going to develop threes. I’m not going to do that.”

Mahinmi won’t suddenly become a spot-up specialist from beyond the arc either, but several Wizards noted his agility after the team’s first training camp practice Tuesday.

“He was moving really well. He’s actually great. To be able to see him healthy,” Bradley Beal said. “He’s lean, in shape and his knees feel good. For a full practice, yeah … he was out here moving and he picked up where he left off last season, for sure.”

Mahinmi’s transformation took a summer commitment. In his world travels — from San Antonio to the West African nation of Benin to his native France — Mahinmi’s entourage included a personal chef and trainers. He wants to remain trim and bouncy because he plans on staying in this league.

“Just for me, longevity,” Mahinmi said. “I want to be playing in this league for another 10 years. I mean, I’m 11 in right now. To me this was, like, necessary. As far as looking at the big picture and looking at my career. Longevity. This was big for me.”

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