Perkins entered the Staples Center Wednesday on crutches, telling reporters he had torn the medial collateral and posterior cruciate ligaments in his right knee while grabbing a rebound in Tuesday's Game 6 against the Lakers, The Boston Globe said.
The announcement ended any speculation he might be able to play in the Finals' deciding game after crumpling to the floor with 5:30 remaining the first quarter of the Celtics' 89-67 blowout loss in Game 6.
"It's crazy," the 6-foot-10, 278-pound Perkins told the Globe. "I bang all the time and come out fine, and this time I get hurt. It's one of those plays you wish you could take back."
Celtics Coach Doc Rivers indicated that while Perkins has yet to undergo an MRI exam, initial tests revealed enough damage to keep him out of Game 7. He said hadn't decided who would replace the big center, who pulled down 35 rebounds in the first six games of the Finals.