BOSTON — Marcus Smart was entertaining teammates with an impossibly spot-on impersonation of former teammate Al Horford at one end of the floor Monday so Jaylen Brown had to know it wasn’t going to be as easy as asking Smart to join his post-practice 1-on-1 work.

See, there’s a science to getting full-intensity Smart when you really want to sharpen your knives. We’ll let Brown explain:

“Ever since I've been here, since my rookie year, I've been trying to take advantage of playing Marcus 1-on-1 and baiting him into playing me,” said Brown. “I’ve been talking trash so that he'll be motivated to play me and I can work on my game.

"Marcus is probably one of the best defenders in the league. Motivated Marcus is tough to score against. But you have to talk a little bit of trash to get him going.”

And if you don’t?

“He might just bull——, or throw up some bull—— [shots],” said Brown. "He’ll laugh and joke but as soon as you start talking trash to him, he’ll be looking to bust your ass. He’ll be super engaged pretty quickly.”

Brown wouldn’t divulge exactly what he said to press Smart’s buttons on Monday but, whatever it was, it had the desired effect. A sweatshirt-clad Smart immediately threw himself full throttle into a rotating game of 1-on-1 against Brown and camp invitee Kaiser Gates.

The frisky 1-on-1 matchups that ensued were maybe more interesting than Boston’s breezy preseason win over Cleveland Sunday and the Brown/Smart battles stole the show. Each player had their moments and Brown bellowed loudly after one successful stop, though it was Smart who had the walk-off moment after muscling home a tough layup with Brown defending.

Marcus Smart with the walk off. pic.twitter.com/V98DGTSwLX — Chris Forsberg (@ChrisForsberg_) October 14, 2019

While many Celtics players scrambled off the floor before the team’s afternoon flight to Cleveland, Brown was one of the last to depart. After the 1-on-1 work with Smart, Brown and Gates shuffled to another court for additional shooting drills. When Gates asked Brown a question about positioning on the way off the court, it spawned yet another round of 1-on-1 battles between the two players who have bonded over shared Atlanta roots.

For Brown, these lengthy workdays — and especially those sessions with Smart — are all part of a plan to dispel a notion that he peaked two seasons ago. He admits he’s frustrated by the notion that he underperformed a year ago during Boston’s train-wreck of a season.

“People always expect better, but the most frustrating thing is people always said that I was having a bad year [last season],” said Brown. “Maybe it was because of the role I was in, or compared to the year before and what I was expected to do, but people always said I had a bad year. I made the best of the situation that I was put in. People always said like, ‘You still had a bad year.' I don't know what else I could have done, to be honest. I don't know.”

His plan, though, is to simply make sure the same can’t be said this time around. Brown politely steers the conversation back to the future when pressed on last year.

“This year I just want to come out and play basketball. That's it,” said Brown. "I think we've got some good guys, we got some talent. … I worked really hard, night in and night out. I watched a lot of film. I'm probably my biggest critic. I just want to come out and just play.”

Celtics coach Brad Stevens believes that last year’s struggles will aid both Brown and Jayson Tatum.

"You should be ever-evolving, you should be ever-growing. That doesn’t mean that the path is not rocky at times. That’s part of it,” said Stevens. "Jaylen, not playing at times during his rookie year, you can see he’s always kind of kept that chip on his shoulder ever since and has always been really good. He’s just gotten better and better. This has been his best preseason.”

Riding some of the momentum he built near the end of the FIBA World Cup in China, Brown has displayed a more complete game this season. He’s sharpened his ball-handling. He’s improved his court vision. He’s stronger and more willing to joust with bigger forward.

Brown is having a particularly efficient preseason despite not shooting the 3-ball well yet. He’s averaging 9 points over just 18 minutes per game while shooting 52.4 percent from the floor overall. The Celtics are plus-47 in his 54 minutes of floor time (most of it from Sunday’s lopsided win) and own an absurd defensive rating of 63.9 when Brown is on the floor. His assist percentage (15.8%) is twice what it was last season (7.9%).

But it’s the eye test that really sells Brown’s improvements. He’s aggressive and confident going at the basket. He’s routinely finishing with his left hand. Brown looks ready to showcase the strides he’s made. He’s eager to show that last season isn’t a reflection of the player he will be.

No, if he can score against Smart, the rest of the league should be no problem.

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