Anthony Davis will undergo further tests today after being forced out of the New Orleans Pelicans' defeat to the Chicago Bulls last night.
The forward fell hard on his right shoulder in the first half of his side's 107-72 loss at the Smoothie King Arena.
While X-rays taken just after the incident came back negative, Davis left the court with his arm in a sling.
Pelicans coach Monty Williams told reporters: "When he goes down like that, your first inclination is to get him out. When a guy hits the floor that hard, you feel bad for him.
"He says he's a bit sore right now. He couldn't move his arm the way he needed to, so we got him out. He kept saying he was okay, but the doctors didn't feel good about getting him back out, so we've got to get more evaluation and we'll have a better update [Sunday]."
Davis has averaged 24.5 points per game for the Pelicans this season.