NEW ORLEANS • Zion Williamson was feted with chants of "M-V-P!" in the fourth quarter from a packed Smoothie King Centre crowd, before he took his seat on the New Orleans Pelicans bench.

As he watched the National Basketball Association game slip away, the home support chanted again, with "We want Zion!" echoing loud and clear in the arena.

That was the story on Wednesday night, when the Pelicans rookie flashed some brilliance in his long-awaited NBA debut, but the San Antonio Spurs spoilt his party with a 121-117 victory.

Williamson, who was the No. 1 overall draft pick in June, offered a tantalising glimpse of what is to come in his career when he exploded for 17 points in little more than three minutes in the fourth period.

The 19-year-old sensation, who had a team-high 22 points, had been sidelined since arthroscopic surgery on his right knee on the eve of the Pelicans' season opener in October.

He made a tentative start, scoring just five points with four rebounds, one assist and four turnovers in less than 12 minutes on the floor over the first three quarters. With 8min 52sec remaining and the Spurs up 99-91, he connected with a three-pointer from the top of the key that ignited the crowd of 18,365.

He followed up with an alley-oop layup, fed by Lonzo Ball, drained a trey and put back his own miss with a spinning layup before adding two more three-pointers.

The crowd was chanting "M-V-P!" (Most Valuable Player) as he capped the burst with a free throw, but he was soon substituted out of the game as Alvin Gentry stuck to the plan of playing him only in short bursts.

"I think what you saw there is a taste," said the Pelicans coach, whose team dropped to 17-28. "There's a lot of potential there."

He said he had counselled Williamson at half-time to be more aggressive, and he was pleased to see him deliver. "I think there's a really, really high ceiling that he can reach, and he can reach it soon," added Gentry.

Williamson, who also had seven rebounds and three assists, admitted that he did not want to be rested just as he had found his rhythm.

"It was very hard," he said. "I'm 19. Honestly, in that moment, I'm not thinking about longevity. I'm thinking about winning that game."

The Spurs, who led by as many as 15 points and by 12 to start the fourth quarter, were up 109-108 when he departed and quickly pulled away again.

LaMarcus Aldridge led the Spurs with 32 points and DeMar DeRozan added 20 for a San Antonio (20-23) team holding down the eighth and final play-off spot in the West.

Williamson, who admitted on Tuesday that he was not sure just how much sleep he would get on the eve of his debut, said that as the pre-game introductions were made, he just told himself to "be calm".

He said it was not just Gentry who urged him at half-time to defer less but also teammates including Jrue Holiday.

"I think he did well," Holiday said, commending the teenager for his poise. "We're almost in February and he hadn't played a game yet, so for him to come out and do that in his first game is pretty elite."

Spurs coach Gregg Popovich was pleased to have a courtside seat for Williamson's debut.

"Oh, yeah, it's great stuff. I'm glad he's back, a talent like that," he said.

"He's a great guy on top of it all. So it's good for the Pelicans. It's good for basketball. He's quite a package as a player and as a person."

AGENCE FRANCE-PRESSE