Yahoo Sports' Adrian Wojnarowski reports the Nets discovered an elbow injury that will take two to four weeks to heal.
N'Diaye signed with the team on Wednesday after playing for Senegal during the 2014 FIBA Basketball World Cup. He averaged 5.7 points, 4 rebounds and 1.8 blocks during the tournament.
N'Diaye spent time last season with the Kings and in the D-League.
- Paul Palladino