Instead, both players failed to leap forward, and so did the Celtics. Boston fell in the second round of the playoffs - just a year after coming within one win of an NBA Finals berth.
While Tatum managed to increase his scoring, rebounding, and passing numbers, his efficiency dropped. The 21-year-old wasn't satisfied with his overall body of work and evidently believes he was capable of producing more this past campaign.
"I want to be one of the best. There's a lot of challenges that come with that," Tatum said, according to The Athletic's Michael Lee. "It's hard to pinpoint one thing from last season. All my stats were better, I did better, just not the jump that I expected and the rest of the world expected."
Brown, meanwhile, was relegated to the bench after a slow start to 2018-19. He averaged 11.1 points on 39.8 percent shooting - including 25.3 percent from distance - across his first 19 appearances.
The 22-year-old regained his starting role in the postseason but failed to replicate his numbers from Boston's previous playoff run, when he was second in team scoring with 18 points per game.
"Experience is the best teacher. Every year and I gain and garner more experience," Brown said. "This year, I look at it as a new canvas. We're artists and it's time to paint."