The rookie had missed over a week of practice after leaving the bubble because of a family emergency. He returned last Friday and cleared quarantine Tuesday before returning to his team for practice.
Head coach Alvin Gentry had said Wednesday that Williamson would be a game-time decision, but he apparently showed enough to be part of the active roster.
Though the forward had practiced the last two days, he missed each of the team's three exhibition games in Orlando, which created concern about his availability.
"I was gone for seven or eight days with an urgent family matter," Williamson said. "Then, I had to sit in a room for four days. The NBA isn't something you can usually just straight into, especially off of stuff like that. So, I think me and my team are gonna look to see what’s best and [see] if I'm ready to go out there."
Even if he is less than 100 percent, the 20-year-old can be a difference-maker.
After missing the start of the season because of a knee injury, Williamson exploded onto the scene with an average of 23.6 points and 6.8 rebounds per game in 19 appearances.
The 2020 No. 1 draft pick entered the league with lofty expectations after an impressive freshman season at Duke, but he has lived up to the hype so far in the NBA.
Playing in the first game will be huge to help New Orleans compete for a playoff spot in the Western Conference. The Pelicans are currently sitting 3.5 games behind the Memphis Grizzlies for the No. 8 seed.