For two of the three, the expectations are clear. Ben Simmons will spend his summer the way his friend and mentor did: building strength, growing into his body, shooting factories-worth of basketballs in an attempt to diversify his offensive game. That has been LeBron James' strategy since he entered the league, and Simmons sounds like a player who understands that he needs to do the same.

Joel Embiid will spend his summer conditioning his 7-foot frame: increasing his stamina, building his muscular endurance, enhancing his agility. Those are the improvements he needs to make to become a back-to-the-basket force while sprinting up and down the court at the Sixers' desired pace.

None of this is revolutionary stuff. As long as they commit themselves to it, their progress as players should follow the same exponential curve as most up-and-coming stars. It's a tantalizing thought — and the biggest reason to think that what the Sixers accomplished this season was the start of something great. Forget the free agents that they will soon try to add or the trades they could explore. In Simmons and Embiid alone, the Sixers have the potential to far exceed the success they produced in this 2017-18 season.

The big question now is what needs to happen for that tandem to become a trio. What, exactly, does Markelle Fultz need to accomplish in the five months before next season?

Sixers (from left) Ben Simmons, Joel Embiid, and Markelle Fultz during a photo shoot before the season.
CHARLES FOX / Staff Photographer
Sixers (from left) Ben Simmons, Joel Embiid, and Markelle Fultz during a photo shoot before the season.

Like every question that has hovered above the rookie's head since the start of the season, it feels impossible to answer. The most confounding thing about Fultz's transformation from a can't-miss No. 1 overall pick to a guy who played in just 17 games as a rookie is the extent to which he and the organization have gone to act as though it's all business as usual. On Thursday, barely 12 hours after he watched the end of the Sixers' season from the end of the bench in Boston, Fultz talked about his coming summer as though the trials of his rookie season were already buried in the past.

"Obviously, I had injuries," he said. "I had stuff that I had to go over. It was God's plan. That's the way it happened. I think I dealt with it fine. And that's how it was."

Which is all well and good, except we still lack a clear understanding of how it is now. After missing five months with a vaguely defined shoulder injury that coincided with the sudden disappearance of his willingness to shoot from long range, Fultz showed some promising signs in the 10 games he played at the end of the regular season. He still had that steady handle and that nose for open space on the court. He showed that he still had the ability to get to the rim and the natural body control to finish. He still has that long frame and those wide hips and that deceptive bounce.

But for all of the raw ingredients that he showed in the 18 minutes he averaged per game, he did not show the one thing that is a prerequisite for spending time on the court with Simmons. He did not show a willingness to shoot from the kind of range required to make this offense work against playoff-caliber competition.

The only three-point attempt of Fultz's rookie season was a rush job at the buzzer at the end of the third quarter of an April 4 win over the Pistons. That's it. One.

Of the 110 shots he attempted, just seven came beyond 16 feet. The average distance on his shot attempts was 6.2 feet — less than the average distance of attempts by Richaun Holmes (7.1), Amir Johnson (6.5), and every guard on the seven other teams in the Eastern Conference playoffs. The only Sixers guard who averaged a shorter distance on his attempts was Simmons, at 5.5 feet. And therein lies the problem.

A backcourt comprised exclusively of players who will not attempt a shot beyond 16 feet is an impossibility in today's NBA. It just won't work. Against the Celtics, the presence of just one such player was enough for Brad Stevens to figure out a way to pour sand in the gears of the Sixers' offensive engine. General manager Bryan Colangelo and coach Brett Brown have a lot of flexibility when it comes to augmenting their roster for next season, thanks to the optionality created by having a guard with the size of Simmons. But the one requirement is that whoever else starts in the backcourt must be able to shoot from well outside of the paint.

Will Markelle Fultz regain the jump shot he had in college?
YONG KIM / Staff Photographer
Will Markelle Fultz regain the jump shot he had in college?

Fultz had that ability in college, and he had it in last year's summer league, and it defies belief to think that a 19-year-old player has lost such a thing forever. But it has been nearly a year since anybody has witnessed that ability in an actual basketball game.

On Thursday, he answered a question about the status of his shoulder and the range on his jumper with the same vague ambiguity we've heard since the onset of the problem.

"It's pretty good, really," Fultz said. "I'm not all the way there, but I definitely have a lot more work to do. Even if I was 100 percent, I would still want to get better. The grind starts now, just to keep working and get better each and every day."

The one thing that's certain is that the Sixers need another starting guard who has a consistent ability to knock down outside shots. As evidenced by the loss to the Celtics, it would be helpful if that player can also match up against athletic guards and create his own shot.

Perhaps, we'll get a better sense of the situation on Friday, when Brown and Colangelo are scheduled to speak with the media. It's difficult to see what can change between now and the start of the free-agent signing period in July.

The Sixers showed this season that their window of opportunity is officially open. If the Fultz situation is still a can of worms, they may already have kicked it as far as it can go.