A few weeks before the NBA postponed its season in March, Boston Celtics forward Jayson Tatum dropped 41 points at Staples Center in a last-possession loss to the Los Angeles Lakers. After the game, LeBron James awarded the NBA's ultimate seal of approval when he posted on Instagram a shot of himself and Tatum, with each looking intently at the court as they waited to check in to the nationally televised matchup.

"That boi to the left of me is an ABSOLUTE PROBLEM!! Keep going," James wrote as the caption, adding the hashtag, "#YoungKing."

Although any narrow loss is dispiriting, a further signal that Tatum is poised to be one of the preeminent stars of his generation is happy compensation.

Nearly six months later, the Absolute Problem leads a team that is once again in the Eastern Conference mix, as the Celtics have continued their forward momentum since breaking ground on their rebuild in 2013. They're on their third All-Star point guard in that span, steady veteran Kemba Walker, but they have a largely young roster without the age and experience of Milwaukee or Toronto.

The Celtics are still developing, still refining their roles in an evolving offense and, in the cases of their pair of dynamic wings, Tatum and Jaylen Brown, still learning which tools to leave in the toolbox. They're rounding into form, and Tatum might find himself on an All-NBA team as soon as this summer. The extent to which the team can accelerate that growth will likely determine the Celtics' postseason fortunes.

Now 2-2 in the Orlando, Florida, bubble after a 149-115 win over the Brooklyn Nets, the Celtics have demonstrated over the course of the season that they do a lot of things well -- not surprising for a team that ranks in the top five in offense and defense. As with any squad, there are natural tension points. This is a good thing because team-building and improvement -- both individual and team -- are accomplished in large part by problem-solving.

Specifically, Tatum's tension point is a product of his budding stardom -- another good problem. He can score a number of ways and is doing so more efficiently this season, but where Tatum thrives in the half court is on isolation possessions. He has grown into a solid pick-and-roll player, but the 22-year-old is lethal if you keep other bodies out of the play and allow him to attack one-on-one. Among the 85 players who have worked in isolation this season more than 100 times, he ranks sixth in points per chance, and he has hit more 3-pointers in iso situations than anyone else other than former MVP James Harden.

Tatum came out rolling on Wednesday. In the first minute of play, he moved left off a Daniel Theis screen and drained a 3-pointer. About a minute later, he caught a skip pass from Gordon Hayward on the left side above the arc. With a single dribble, Tatum flew by Caris LeVert, then elevated above Joe Harris to scoop the ball off the glass for an easy 2-pointer -- easy for Tatum, at least. After picking up two quick fouls, Tatum was sidelined for much of the first half. With the game in hand, Brad Stevens sat his superstar for the fourth quarter on the second night of a back-to-back -- but not before Tatum drained five 3-pointers in eight attempts. He finished with 19 points in 18 minutes.

Tatum's iso exploits occur outside the confines of a Celtics system that relies on the active engagement of all five players on the floor. Organization is one of the strengths of the Celtics' offense, but staying organized requires some compromise. The trick for Tatum? Choosing his iso opportunities at his best spots against the best matchups, then expanding his repertoire. A dynamic scorer draws a ton of attention, which means there's offense to be created for the other four guys. When Tatum kicks the ball out and relocates, the Celtics can put defenses in a blender. The same is true if Tatum is flying around stagger-screens off the ball. He still gets a steady diet of shots, and four other Celtics can flow in motion (think Paul George during his leap and beyond). Everybody wins.

Brown is a fascinating complement to Tatum. A Swiss army knife, Brown generates most of his shots within the flow of the offense, much like teammate Marcus Smart. With each passing season, he's using his exceptional strength to get to his spots -- more out of Kawhi Leonard's book than George's. Importantly, he doesn't lose his game or confidence if the ball doesn't come to him. Successful teams need generalists like Brown, who carry a rare combination of confidence and selflessness.

An exhibition of Brown's strength generating opportunities for himself outside the confines of a set offense came just before halftime Wednesday. On a broken play, Smart corralled a loose ball and drove, only to meet a couple of Nets defenders and kick the ball out to Brown on the perimeter. With a little shot fake, Brown squeezed through a couple of defenders, then bumped off two more underneath the basket to muscle a layup off the glass. He finished with a game-high 21 points, including a torrid 5-for-9 night from 3-point range.

Both Tatum and Brown are linchpins of a disciplined, tight defense that starts with Smart, and this is a key part of their appeal. The Celtics have the switchiest defense in the East, per Second Spectrum, which is no surprise given the personnel. When opponents look to attack Walker, the Celtics are expert at switching back to kick him out of the matchup. Apart from Walker and big man Theis, the like-sized core (including the 6-foot-3 Smart, who is a transformer who can play as big or small as you like defensively) is suited to a modern NBA that rewards versatility. A defense can certainly thrive with a Rudy Gobert, Brook Lopez or Joel Embiid, but as league offenses increasingly abandon the paint, the Golden State model of a collection of lengthy, stalwart, 6-foot-7 defenders can present as many problems.

When we think of teams who craft their game plans for a bunch of big, perimeter, skill players who can shoot, Boston isn't the first that comes to mind. Yet the Celtics' five best players -- Walker, Smart, Tatum, Brown and Hayward -- make up one of the NBA's most adaptable teams on both sides of the ball. All but Smart shoot greater than 38% from beyond the arc (Smart hovers at 35%). Each has an adequate handle that can initiate offense, and each can switch onto almost any NBA matchup.

The most interesting question for the Celtics headed into the postseason is how aggressively they will deploy that "Best Five" unit. In 3 minutes, 28 seconds Tuesday against Miami, the Heat's Bam Adebayo exploited the matchup, with seven points during that brief stretch, including eight free throw attempts. More disappointingly, the Celtics converted only one field goal.

Utilizing the Best Five lineup will be a test of faith for Stevens. It's a great unknown (the players recorded only 15 minutes together prior to the bubble this season) with considerable upside and downside. In an ideal world, the Best Five will stretch defenses to their limit, bombing away from long distance and driving with force when those defenses close out with abandon. In a catastrophic world, the Celtics will miss Theis' size and presence, as well as his Marcin Gortat-esque screening genius -- consequently producing more outcomes like Tuesday.

The Celtics' uneven performance during the first week of the bubble is of limited concern. Walker continues to work his way back from a knee injury -- he sat out Wednesday night's back-to-back -- and Stevens emphasized after Tuesday's loss that the careful management of Walker's minutes in Orlando is a reflection more of caution than concern.

"He's continuing to strengthen right now," Stevens said. "When he plays a couple of games in the 30s [minutes], he'll feel better about it. By then, in the playoffs, he'll be fine."

Walker's pick-and-roll mastery will be a crucial ingredient in Boston's playoff run, along with Smart's ability to contain and emotional leadership and the healthy Hayward's second-side playmaking. But the Celtics' 2019-20 season -- and their promising future -- rests on the continuing maturation of Tatum and Brown.

The front office's objective in accumulating a trove of draft picks over the course of their rebuild was always simple, even if their procurement was complex: Turn those assets into championship-caliber stars. With Tatum and Brown, the Celtics are making good on that goal. The summer of 2020 will be the biggest test yet.