Julius Erving was taken to hospital after becoming ill while attending the Philadelphia 76ers' home game against the Detroit Pistons on Friday.
A report issued by the 76ers and Erving's management team says he is expected to be released.
"He is currently being evaluated. He is expected to be released after the evaluation," read the statement (via Philly.com).
The 67-year-old NBA legend, who played 11 of his 16 pro basketball seasons in Philadelphia and led the team to the 1983 NBA championship, was at the 76ers' home game as the ceremonial bell ringer before the game.
Erving is the NBA's seventh all-time leading scorer with 30,026 points. Beyond that, his showmanship and high-flying style of play revolutionised the game and helped pave the way for later stars such as Michael Jordan, Vince Carter and Kobe Bryant.