New Cavs center Andrew Bogut broke his left leg in the second quarter and had to be assisted off the floor and to Cleveland's locker room.
The Cavs said initial X-rays revealed a fractured left tibia. Bogut is at the Cleveland Clinic undergoing further tests.
The 32-year-old sustained the injury at the 11:38 mark of the second quarter of the Cavaliers' 106-98 loss to Miami, just moments after taking the floor for the first time in his No. 6 jersey.