NEWPORT, R.I. - Marcus Smart is walking around a lot more with his shirt off. And it may be a positive sign for the Boston Celtics this season.
The fourth-year guard developed a reputation as one of the Celtics' toughest players in his first three years in the NBA. While filling primarily a sixth man role during the past two seasons, he was often called on to be an energy guy and defensive stopper.
But carrying at a less-than-svelte 240 pounds on his 6-foot-4 frame started to take a toll on him last season. Throughout Boston's entire postseason run Smart found himself dogged by back problems.
''Before games, during games, after games - it was hard for me to go to sleep,'' he recalled.
He also didn't like what he saw in the mirror.
''I remember times putting on my shirt and having to tuck my stomach in because I didn't like the way it looked,'' he said. ''That pain (his back) was causing me, I was tired, I wasn't as explosive.''
He also found himself needing more energy just to do the things that had once come so effortlessly during his basketball career. It served as a wakeup call for the 23-year-old entering the offseason.
''I wasn't too fond of that,'' Smart said. ''I didn't like it one bit and I knew I had to change.''
Change he has. He got a personal chef this summer, changed his diet, and arrived for training camp 20 pounds lighter. That midsection flab he once hid is now all muscle.
It's a welcomed sight not only for Smart, but for president of basketball operations Danny Ainge. The Celtics' front office chief said part of the organization's goal for Smart was to see him slim down.
''Umm, yes,'' Ainge said when asked if they wanted Smart to lose weight. ''But, listen, Marcus wanted to also. He's worked extremely hard ... on his eating and his sleeping and his basketball development. I credit Marcus, mostly, for just really wanting it and putting in the time.''
The weight loss has also given Smart more confidence.
''He's wearing his tank top around. Sometimes takes his shirt off. `Hey Marcus, put your shirt back on. We see the six-pack,''' Ainge said. ''But seriously, it's fun to see. He's got guys throwing alley oops to him in pickup games ... I'm hoping that leads to a great year for him.''
Part of Smart's tough guy persona is the result of his propensity to get under the skin of some of the NBA's best players. One example came last season during the playoffs, when he had a brief dustup with Jimmy Butler during Boston's first-round matchup with Chicago. It led Butler to accuse Smart of being a fake tough guy.
Smart laughed the incident off and responded the next game with probably his most complete outing of the series: Eight points, eight assists, three rebounds, a steal and a block. For the season he also averaged career-highs in points (10.6) assists (4.6) and minutes (30.4).
It why after all of the massive changes Ainge made to his roster this summer, it was no coincidence that Smart was one of the four holdovers, along with Al Horford, Terry Rozier and Jaylen Brown.
Brown said Smart is hardly recognizable.
''He looks good, man. He's moving a lot faster. He's jumping a lot higher. It's kind of weird to see him like that,'' Brown said. ''Just imagine, you see him and he's like 25 lighter. It's like, `Man, who is this guy?'''
Coach Brad Stevens thinks the changes will help Smart take his game to the next level.
''Marcus is a critical part of our team,'' Stevens said. ''I think ultimately we want our identity to be a team that gets better every day. And I think his mindset, his competitive spirit, his toughness, his will - all of those things make teams better.''
One thing that won't change, Smart said, is how he plays the game. His physique has changed, along with many of the players around him. But the goals are the same, even has he prepares to take on a new role as one the Celtics' veterans.
After all the offseason changes, he is now the Celtics' longest-tenured player.