It felt sad, like watching a dancer try to remember how to pirouette.

Even later on this recent evening, when he was surrounded by his well-wishing, backslapping teammates before a game against the Charlotte Hornets, it felt melancholy. Markelle Fultz, only 19, was on the margins, an outsider. He hadn’t played in a league game since October. The 76ers were having their best year in recent memory, but Fultz, their wunderkind, has had nothing to do with it. He might play again this season, but it doesn’t seem likely.

You could see the burden. This was supposed to have been the start of a can’t-miss professional career. His shoulders slumped. He shook his head in disbelief. He sank his 6-foot-4 frame into a padded blue chair and watched his fellow Sixers warm-up. Every shot they took had rhythmic confidence.

Last season, his only year in college, at the University of Washington, Fultz made basketball look easy. He was one of the nation’s leading scorers. His jump shot was slightly awkward, but deadly accurate. On his three-pointers, he hit 41 percent — exceptional under any circumstance. But more so because he was the only star on a moribund team. Opposing defenses swarmed him like wasps.

The 76ers became enchanted by his ability to score, pass and dissect the game. They traded for the No. 1 pick to get him.

He would be the capstone of the Sixers’ long, arduous rebuild. It was called the Process — a gambit that used losing as a way to position Philadelphia for upper-tier draft choices. The Process was a bumpy ride, but the 76ers, their fans, and astute N.B.A. insiders said adding Fultz to a lineup alongside Joel Embiid and Ben Simmons was the making of a team that could win a championship.