It’s no coincidence that, two days after Marcus Smart lamented how opponents no longer fear the Celtics, his coach not only thrust him into the starting lineup but played him a whopping 40 minutes during Boston’s triumph Monday night in New Orleans.



It was only the fifth time since the start of the 2016-17 season that Stevens has utilized a player for 40-plus minutes in a non-overtime, regular-season game. Stevens works hard to limit his players’ minutes, especially in a situation like Monday when Boston was playing its third game in four nights on the road.



But running Smart so long sent a clear message to his team about the energy and intensity the coach desires as the Celtics try to get on track. Smart’s efforts helped Boston produce some of its most inspired two-way basketball of the season, offering both a flashback to what made this team so successful last season and a glimpse of how good the Celtics can be moving forward when they prioritize defense and hustle.



For all their obvious skill, particularly with the return of Kyrie Irving and Gordon Hayward, these Celtics are still at their best when they play gritty. It’s why Smart, despite his offensive warts, remains the heart and soul of this team.



What’s more, on a team full of quiet leaders, Smart is the one person who won’t sit quietly when things go awry. That’s why he deemed Boston’s uneven play unacceptable at the end of a woeful West Coast road trip earlier this month, then sounded off about how Boston had lost its identity after a disheartening loss on Saturday in Dallas.

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If Smart came out and got torched by Jrue Holiday on Monday night, his words would have rung hollow. How can players trust someone who spouts off but doesn’t back it up? Just the opposite, Smart set an immediate tone during Monday’s game with his defensive intensity and rarely relented while steering Boston to a 124-107 triumph it so desperately needed while at risk of dipping below .500.



Stevens doesn’t like the idea of captains, but on a team where Irving and Al Horford are leaders based on their talent and experience, you get the sense that Smart might just be the glue to this whole thing.



There was a possession about three minutes into Monday’s game where Anthony Davis had a free run down the lane after Jayson Tatum and Al Horford tried to trap Holiday on a pick-and-roll near the elbow. Smart ditched his man in the corner and not only picked up Davis in the paint but then picked off a careless Holiday feed and went coast-to-coast for a layup that capped an early 10-0 burst.



Smart was relentless fighting through screens and applying ball pressure on Monday night. According to the NBA’s defensive tracking data, he forced Holiday into five turnovers while defending him on 38 possessions. What’s more, Smart spent 10 total possessions defending Davis and Nikola Mirotic and allowed only 2 points.



Smart hasn’t been perfect defensively this season and he was gouged by Kemba Walker during a loss in Charlotte this month. But he’s been far and away the team’s most consistent defender and his energy on that end is simply infectious with those stops often leading to easy transition opportunities for a Celtics team desperate for more offensive consistency.

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Smart is allowing 0.8 points per play this season, according to Synergy Sports defensive data. That ranks in the 84th percentile among all NBA players, but narrow to the 84 players with at least 200 total possessions defended and Smart ranks eighth overall. The only other guards in the top 10 are Holiday (0.76) and Mike Conley (0.659).



Go ahead and lament Smart’s shot selection and offensive struggles (he’s averaging 6.4 points on 37.5 percent shooting overall) but for a Celtics team with a wildly inconsistent offense overall, he’s the perfect reminder that you can still be impactful when your shot doesn’t fall.



And it's the most Smart thing ever that Boston is 9-4 this season when he shoots 40 percent or worse during a game, and 2-6 when he shoots better than 40 percent.



In fact, Smart’s win splits (5.4 points / 33.3 FG% / 22.6 3PT%) are notably worse than his loss splits (7.6 points / 41 FG% / 38.9 3PT%). The only plausible explanation seems to be that offensive woes might make him work even harder on the defensive end.



Regardless, Smart was worth every cent of the four-year, $52 million pact he signed as a restricted free agent this past summer. The Celtics could have squeezed him on a quiet market, maybe even forcing him to play at the qualifying offer, before letting him explore unrestricted free agency this summer. Instead, they worked to ensure he’d be back and with the potential for a long-term partnership.



Given the way Irving glowed about having Smart alongside on Monday night, it seems a strong bet that Smart will continue to get first-unit reps while Jaylen Brown recovers from a back bruise after a hard fall in Dallas. Regardless of his role, Monday was a reminder that Smart being on the floor for big minutes typically leads to good things for the Celtics. Boston is 4-1 this season when Smart plays 27 minutes or more.



The Celtics still have an awful lot of wrinkles to iron out but one thing is clear: An extra scoop of Smart tends to go a long way towards making things better.

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