Zion Williamson is expected to miss six-to-eight weeks after undergoing knee surgery on Monday, the New Orleans Pelicans have announced.

New Orleans said the top overall pick in the 2019 NBA Draft had an arthroscopic procedure to repair a torn lateral meniscus in his right knee.

Williamson missed last Friday's preseason finale against the New York Knicks due to "right knee soreness".

Pelicans coach Alvin Gentry told reporters the team believes Williamson hurt his knee earlier this month against the San Antonio Spurs.

Williamson averaged 23.3 points in four preseason games.